Assurance

So that you may know

John tells his readers why he wrote:

I have written these things to you who believe in the name of the Son of God, so that you may know that you have eternal life.

1 John 5:13

God does not mean his children to live in dread. Believers did not receive "a spirit of slavery that returns you to fear" but the Spirit of adoption (Romans 8:15), and "The Spirit Himself testifies with our spirit that we are God’s children" (Romans 8:16). Hebrews urges us to draw near "in full assurance of faith" (Hebrews 10:22); the word, plērophoria (πληροφορία), means a settled, full conviction.

Assurance rests first on what God has promised in Christ. The Spirit's witness confirms it, and a changed life bears it out: "By this we can be sure that we have come to know Him: if we keep His commandments" (1 John 2:3). Yet John also knows that our hearts sometimes accuse us, and answers, "God is greater than our hearts, and He knows all things" (1 John 3:20). Assurance comes less from measuring our progress than from looking to Christ. It grows with faith, and it is closely tied to the teaching that God keeps his people to the end, the perseverance of the saints.

What the church has said

The Reformers taught that true faith includes a personal trust that God's promise is for me. The Heidelberg Catechism defines faith as:

a hearty trust which the Holy Ghost works in me by the Gospel, that not only to others, but to me also, forgiveness of sins, everlasting righteousness and salvation, are freely given by God, merely of grace, only for the sake of Christ's merits.

Heidelberg Catechism, Q. 21

John Calvin likewise defined faith as a firm and certain knowledge of God's goodwill toward us, founded on the free promise in Christ and sealed on our hearts by the Spirit Calvin, Institutes 3.2.7. The Westminster Confession, shaped by long pastoral experience, adds that this assurance "doth not so belong to the essence of faith, but that a true believer may wait long, and conflict with many difficulties before he be partaker of it" Westminster Confession 18.3. It may be shaken and later revived by the Spirit 18.4; meanwhile believers are to "strive to make your calling and election sure" (2 Peter 1:10).

John Wesley stressed the Spirit's direct witness, which he described as "a testimony distinct from that of his own spirit, or the testimony of a good conscience" Wesley. He came to teach assurance as the common privilege of believers, while refusing to condemn those whose assurance was weak.

Where the traditions differ

The Catholic Church calls believers to firm hope in God's mercy and promises, but the Council of Trent taught that no one can know with a certainty of faith that cannot err that he has obtained God's grace Council of Trent, Decree on Justification. The Orthodox churches, seeing salvation as a lifelong path, usually speak of hope and humble trust in God's mercy rather than of certainty.

Evangelicals differ in emphasis among themselves: how far assurance belongs to faith itself, and how much the Spirit's witness is to be expected as an experience of the heart, are answered differently in the Reformed and Wesleyan traditions. All of them warn against false assurance. Jonathan Edwards taught that true religious affections prove themselves in the fruit of a holy life Edwards, Religious Affections. See also the lessons Effectual calling and perseverance and Wesley and the Methodist movement.