The Protestant Reformation of the sixteenth century—the beginnings of which are usually associated with the work of Martin Luther (1483–1546)—was really a collection of reformations across Europe. Various reformations of the church, theology, public worship, and even the broader society took place in nations including Germany, Switzerland, the Netherlands, Scotland, and England. Originally intended to reform the Western church from within, the Reformation led to a self-conscious effort to abandon the trappings of Roman Catholicism so that a true church might continue, since the Roman Catholic church had rejected vital theological reforms. Today, the theological principles of the Reformation may be summarized by the five solas—namely, that sinners are saved by grace alone, through faith alone, in Christ alone, under the authority of God’s Word alone, and all to the glory of God alone.

The Federal Vision was a theological movement that caused controversy within Reformed churches during the first decade of the twenty-first century. The Federal Vision (also known as Auburn Avenue Theology) gained traction when a small group of pastors began to teach substantial revisions to historic covenant theology. While proponents of the Federal Vision did not all share the same theological commitments, they collectively sought to recast historic covenant theology as understood in the standard Reformed confessions. Federal Vision proponents tended to focus on the objectivity of the covenant of grace, downplay the distinction between law and gospel, conflate the visible church and the invisible church, assert presumptive regeneration or baptismal regeneration, embrace a functional sacramentalism, affirm paedocommunion, deny the covenant of works, reject the imputation of Christ’s active obedience, and promote the idea of a final justification based on Spirit-wrought good works. Out of concern for the impact of this revisionist movement, numerous Reformed churches formed study committees to report on its theological problems. In the second decade of the twenty-first century, the momentum of the Federal Vision was severely weakened by the trajectories of some of its more prominent adherents.

The Puritans of the sixteenth and seventeenth centuries sought to bring about a more thorough Reformation in England—to purify the English church from any Roman Catholic vestiges—especially in the areas of theology, worship, and personal holiness. Originally used pejoratively, the term Puritan referred to one who, politically, reacted against the via media (middle way) of the Elizabethan Settlement; who, theologically, held the Reformed views of the five solas and (usually) the doctrines of grace summarized by the acronym TULIP; and who was committed to discipleship, evangelism, an experiential faith, communion with God, and personal piety. Despite their commonalities, there was no unified Puritan view on topics such as church government and baptism. While there has been much debate over the exact dates of the Puritan movement, Puritanism flourished between 1558 and 1689 in England and during the early eighteenth century in America.

The twentieth century was a period during which professing Christians reacted to cultural and religious challenges stemming from the late nineteenth century and developed unique contours of faith and church life that are still prominent today. The rise of social and economic global connectivity during the twentieth century not only provided a test of faith through two World Wars, the Great Depression, and the heights of communism, but it also provided particular opportunities for the gospel of Jesus Christ to be spread throughout the world. Although the religious landscape looked considerably different at the end of the twentieth century than it did at the beginning, God continued to preserve the historic, biblical Christian faith among His people.

During the seventeenth century, the massive theological and ecclesiastical shifts hammered out during the sixteenth-century Protestant Reformation were solidified and codified. This was the era in which some of the greatest Reformed confessions and catechisms were written and in which Puritanism began to exercise a decisive influence in England and in North America. Denominations as we know them today began to develop and there was much conflict between church and state regarding the state’s role in the life of the church.

No one who trusts in Jesus Christ will be eternally lost. Jesus said, “All that the Father gives to me will come to me, and whoever comes to me I will never cast out” (John 6:37). Anyone who has come to Christ belongs to Christ forever. Everyone who has faith in Christ has eternal life (John 6:40).

Yet Christians often fear that they have not really come to Christ. They want assurance that their faith is real. They want to know for sure that they are God’s children. The Bible teaches that this desire for assurance conforms to God’s will for His people. God wants believers to know that their faith is genuine. He wants them to be sure that they belong to Him and have eternal life through Christ.

Gender-neutral language in the field of Bible translation refers to grammatically masculine words in the original languages of Scripture being rendered with non-gender-specific glosses in English translations. In some cases, this is a result of differences between modern English and the biblical languages, and certain gender-neutral glosses provide a legitimate translation of Hebrew and Greek nouns and pronouns when they represent both males and females. As a result, some amount of gender neutrality is employed by every English translation of Scripture. In other cases, however, translators have used gender-neutral language in such a way that it erodes the integrity of the resulting translation.

The question of gender-neutral language became controversial in the late twentieth and early twenty-first centuries as translators and publishers sought to adapt their translation of nouns and pronouns to contemporary changes in the English language. This resulted in the gender-neutral controversy, a debate among evangelical and Reformed theologians over Bible translation theory and philosophy. In the 1990s, certain translators produced intentionally gender-neutral translations, purposefully introducing egalitarian agendas into their translation of masculine nouns and pronouns. One of the more controversial Bible translations was the 1996 New International Version Inclusive Language Edition (NIVI). The gender-neutral controversy manifested itself in evangelical circles on account of debates over gender wars between egalitarians and complementarians. This debate also exposed disagreements among complementarians over historical understandings of the Trinity.

Theonomy is a political-theological movement that arose within Reformed theological circles in the 1970s. It is also known as “Christian reconstructionism,” “dominion theology,” or “general equity theonomy.” While differences exist among proponents, there is a common commitment to the belief that God requires the implementation of old covenant civil laws in the governments of the nations during the new covenant era. Theonomists reject the notion that the judicial laws God gave to Israel in the old covenant have expired in the new covenant.

In the Gospels, Jesus called those who believed His teachings disciples (Matt. 9:14; 16:24; Mark 2:16). After His resurrection, He gave these believers a mission: “All authority in heaven and on earth has been given to me. Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, teaching them to observe all that I have commanded you” (Matt. 28:18–20).

Jesus made disciples. Then, as He prepared to return to heaven, He told these disciples to “make disciples.” But what are disciples? And how does Jesus say they are made?

The medieval church period spanned roughly one thousand years (AD 500–1500) and produced several figures and ideas that continue to influence the church today. This era—the name of which is derived from the Latin phrase medium aevum (middle age)—began with the fall of the Western Roman Empire and ended roughly with the beginning of the Renaissance and the Protestant Reformation. During the medieval era of church history, the power of the papacy grew, and the biblical gospel was slowly eclipsed, although several individual thinkers made important contributions to our theological understanding. The full-orbed truth of the gospel would not be restored to a prominent place in the church until the Protestant Reformation. Nevertheless, God preserved His remnant throughout the medieval church period.

Holiness is an attribute of the triune God. The full scope of divine holiness is complex, which is why there have been multiple ways of describing God’s holiness, including that it refers to separateness, otherness, purity, moral perfection, or the radiance of God’s perfections. God is infinitely, eternally, and unchangeably holy; nevertheless, holiness is also an attribute that God communicates to believers by the Holy Spirit in a manner that allows them to reflect the character of their holy Creator. At creation, God made man in a condition of holiness and entered into a covenant of works with him. In the Old Testament, God manifested His holiness in His judgments, in His covenants, and in the cultic practices that He gave to old covenant Israel. In the New Testament, God reveals His holiness fully in the person and work of Christ. Because of the saving work of Christ, God grants positional holiness to those who have been united to Christ by faith, and He works in them a practical holiness whereby the Spirit transforms them into the likeness of Jesus. In the consummation, God will reign supreme in a perfect display of His holiness for all eternity with the whole host of redeemed men and unfallen angels.

God’s grace is the manifestation of His goodness toward His creation. In Scripture, God’s gracious disposition to sinners is revealed immediately after the fall, wherein Adam failed to fulfill the covenant of works. In the Old Testament, God exhibited His grace in the various historical administrations of the covenant of grace. In the New Testament, the gospel further reveals that these types and shadows point to Christ through whom God extends His saving grace to His people.

Throughout church history there have been significant debates over the doctrine of grace. In the fifth century, a sharp dispute arose over the nature of God’s grace. Augustine became the principal defender of God’s sovereign grace in his debates with Pelagius. During the Reformation, a sharp debate emerged between Roman Catholic and Reformed theologians over the meaning of God’s grace. Rome taught a meritorious or quasi-meritorious view of grace. The Reformers defended the biblical teaching of the unmerited nature of grace and also described the two classifications of God’s grace—namely, common grace and special or saving grace.

Scripture reveals that there will be a day on which God will judge angels and all mankind through His Son, Jesus Christ. When Christ comes again in glory, He will bring about the resurrection of the just and the unjust. The final judgment will occur immediately after the resurrection. Judgment day will be a day of both salvation and judgment. It is commonly referred to in the Old Testament as “the day of the Lord” (Isa. 13:9; Ezek. 30:3). Believers have already passed through judgment based on the sinless life, atoning death, and resurrection of Christ. On judgment day, God will condemn unbelievers to eternal perdition, based on their own sinful thoughts, words, and works. Though there is no punitive judgment for believers on account of their union with Christ, there will be an accounting of the deeds done by believers, resulting in the distribution of rewards in accord with their faithful labors. These rewards are to be considered in addition to the eternal life they have already received through faith in Christ alone. In other words, people receive salvation only through faith in Christ and do not merit eternal life, but God gives additional rewards that differ from person to person depending on the individual’s obedience. This day and hour of judgement is unknown to mankind for the express purpose of encouraging God’s people to be watchful and prayerful (Matt. 24:36).

God’s glory is the outward manifestation of His perfection and the expression of the weight, value, and importance of His being and character. God’s glory is manifested in His works of creation, providence, and redemption. The glory of God is revealed in the display of His wisdom, power, and goodness in creation and providence. In the history of redemption, God’s glory was revealed in numerous types and shadows that pointed the Old Testament people of God to the coming of the Savior. In the fullness of time, God’s glory was revealed in the incarnate Son of God and the work of the triune God at the cross for the redemption of the elect. Since He is the glory of God, Jesus will ultimately glorify all those He came to redeem. The Gospels give a glimpse of Christ’s eternal divine glory at the transfiguration. The book of Revelation presents a vision of the eternal glory of God in the new heavens and new earth.

Baptism is a sacrament sovereignly instituted by God to be a sign and seal of the new covenant. Through a symbolic washing with water, the Lord signifies and seals the covenant promises to forgive, cleanse, and renew His covenant people. The meaning of baptism is rooted in the meaning of the covenant signs in the Old Testament. In the new covenant, baptism has replaced the old covenant sign of circumcision. Both sacraments signified membership in the visible church. Both point to the promise of redemption through the shed blood of Jesus. As a preparatory sign in redemptive history, circumcision was a bloody rite that pointed to the death of the Savior. After Christ shed His blood at Calvary, there was need for a new sign of initiation into the new Israel. Accordingly, Christ instituted the sign of baptism to be the unbloody sign of the new covenant. The proper recipients of baptism are all who profess faith in Christ, together with their children.

The Enlightenment and modernism—spanning the revolutionary and turbulent period from the late seventeenth century to the early nineteenth century in Europe and America—represented a philosophical, intellectual, and religious shift from the historical Christian understanding of faith and reason. While some thinkers have maintained that the Enlightenment and modernism were two separate movements, it may be more accurate to identify modernism as a worldview birthed by the Enlightenment movement, though the two terms may be used interchangeably. Proponents of Enlightenment and modernist ideals pitted science against religion and argued for the primacy of human reason, the inevitability of human progress, and the separation of church and state. They sought freedom from what they saw as the trappings of traditional social ethics, art, music, learning, and faith, advocating a worldview that saw all things existing and prospering apart from God and His special revelation in the Bible. Man, not God, was embraced as the measure of all things.

During the eighteenth century, the Enlightenment, the First Great Awakening, revolutions in both America and in Europe, missionary expansion, and musical development all left their mark on the church. The principles and ideals forged in the furnace of the religious and societal upheaval brought about by the Renaissance, the Protestant Reformation, and the colonization of the New World during the sixteenth and seventeenth centuries continued to reverberate. Many significant events and people reshaped the church, with effects lasting to the present day.

The Lordship Controversy occurred in the last two decades of the twentieth century. It was a debate largely between dispensational theologians regarding the nature of salvation and the place of repentance in the life of true believers. On one side of the Lordship Controversy was a company of “Free Grace” theologians who denied that repentance and obedience are necessary in the Christian life. On the other side of the controversy was a group of Calvinistic theologians who taught that although salvation is based only on God’s sovereign grace, God requires the evangelical response of repentance and faith in our reception of the gospel. The latter emphasized the importance of the lordship of Christ in reaction to the denial of the need for repentance and the fruit of obedience in the teaching of the proponents of the Free Grace movement. By undermining the place of repentance and good works in the life of a believer, proponents of the Free Grace movement essentially advanced an antinomian view of justification. Although there was enough uniformity on each side of the debate to label these two different positions, there were also nuances in the way in which individual figures articulated the dynamics of both the Free Grace and the Lordship Salvation approach to the doctrine of salvation.

The word joy appears nearly two hundred times throughout Scripture. The Old Testament is filled with references to joy, from the psalmist who “shout[s] to God with loud songs of joy” to the prophet Isaiah describing “everlasting joy” (Ps. 47:1; Isa. 35:10). When we come to the New Testament, the Apostle Paul reminds believers that joy is a fruit of the Holy Spirit, a virtue present within Christian believers (Gal. 5:22). Joy is not to be confused with happiness, which is often based on favorable circumstances. True abiding joy is a feeling within believers of inner gladness, delight, or rejoicing despite circumstances.

Fasting means to abstain from eating and/or drinking as an act of personal and corporate piety. It is common in religions around the world, but in the Christian faith, it holds special significance and can be seen throughout Scripture. During His earthly life, Jesus corrected and clarified the purpose and role of fasting (Matt. 5:16–18; 9:14–16).

Scripture has much to say about strength. The prophet Isaiah called out, “The Lord God is my strength and my song” (Isa. 12:2). Jesus commands His followers to love God “with all your soul and with all your mind and with all your strength” (Mark. 12:30). Paul alludes to the fact that we are strengthened by spiritual gifts (Rom. 1:11). Paul confirmed to young Timothy that he was strengthened by the Lord for the preaching of the truth (2 Tim. 4:17). Perhaps one of the most well-known passages about strength is Philippians 4:13: “I can do all things through him who strengthens me.” According to all these passages, the origin of our strength is God. The psalmist wrote, “Be strong, and let your heart take courage, all you who wait for the Lord” (Ps. 31:24). Isaiah said that the Lord “gives power to the faint, and to him who has no might he increases strength” (Isa. 40:29).

Dispensationalism is a modern hermeneutical system of theology that exists as an alternative to historic Reformed covenant theology. Dispensationalism originated in the nineteenth century in the writings of John Nelson Darby. It has spread rapidly throughout the church in the Western world since in the second half of the nineteenth century. So widespread was its reception that the majority of evangelicals in the United States and Britain came to embrace some elements of it. The flourishing of dispensationalism in the twentieth century was due largely to the advent of “prophecy conferences,” the widespread use of the Scofield Study Bible, and the establishment of dispensational Bible institutes and colleges. There are three distinct characteristics of dispensationalism: a sharp distinction between Israel and the church, the division of the history of salvation into dispensations, and a woodenly literal hermeneutic regarding biblical prophecy and apocalyptic literature. At the end of the twentieth century, refinements made to classical dispensationalism resulted in the propagation of progressive dispensationalism, which makes many of the traditional dispensational distinctions but also sees greater continuity overall between the various dispensations and between old covenant Israel and the new covenant church.

The New Perspective on Paul is a theological movement that achieved widespread popularity in the first decade of the twenty-first century. While the viewpoints among New Perspective proponents are not monolithic, all generally insist that the teaching of second temple Judaism should be the guiding standard for understanding the background of Pauline theology. New Perspective adherents also generally believe that historic Protestantism has fundamentally misread the Apostle Paul by reading Reformation-era debates back into his works. Consequently, theologians of the New Perspective have recast the Reformed understanding of justification and the gospel. Some New Perspective scholars have offered readings of Paul that are not substantially different from interpretations of Paul proposed by Roman Catholic theologians during the Reformation. Many New Perspective thinkers have asserted that “the gospel” is not the message about how an individual is saved; rather, it is has to do with how one identifies the members of the new covenant community. These theologians radically redefined the Protestant and Reformed doctrine of justification by faith alone. Many Reformed theologians offered strong and nuanced critiques of the New Perspective throughout the first two decades of the twenty-first century.

Creationism teaches that the eternal, self-existent God created the universe, and this doctrine is attested to throughout the Old and New Testaments as a foundation of the faith. It stands as the first doctrine revealed in Scripture. The doctrine of creation makes a sharp distinction between the Creator and the creature. The triune God has revealed Himself to be the Creator of the heavens and the earth. God reveals His attributes in the creation of the universe. With the advent of the evolutionary theory of origins, creationism became a controversial doctrine. The materialistic and naturalistic worldview of evolution stands in stark opposition to the biblical doctrine of creation. Modern secular scientific theories in astronomy, biology, and geology have attempted to bolster a naturalistic worldview.

Although Christians have agreed that God created ex nihilo, “out of nothing,” there has been some disagreement on issues such as the age of the earth and what the six days of creation in Genesis 1 signify. One of the most widely held positions is that Genesis 1 teaches that God created everything in six ordinary twenty-four-hour days. Since the advent of scientific theories of origin and material aging, more proposals have been raised. Today, we can make a distinction between young-earth creationism and old-earth creationism. Young-earth creationists hold that the created order is relatively young, perhaps no more than about ten thousand years old. Old-earth creationists believe that the universe is much older, being millions or even billions of years old.