Trust, especially in the reliability of God. A modern misunderstanding of faith is that it is an inferior kind of knowledge or an acceptance of an opinion or story which cannot be wholly proved. The biblical meaning of faith (the corresponding verb is ‘believe’) is more in the nature of commitment, though it does also imply that there is a basis in fact which could, by virtue of conclusive historical evidence, render faith unsupportable. OT faith was traced to the covenant which God had offered to the people of Israel at Sinai. From then on, the Israelites believed that Yahweh, the creator of the world, had given them the Law and a promise that their faithfulness would be rewarded. Without such a faith, the people of Israel would not survive, as the prophets warned (Isa. 30: 15–16). Individual Israelites also have faith: a trust that the righteous have in God, come what may (Ps. 73: 1–3); and sometimes an individual's faith is related to the destiny of the nation, as it was with Abraham (Gen. 15: 6), who believed in God when he was called to leave his country, and when he was promised an heir though he was beyond the normal age of procreation, and yet again when he obeyed the call to sacrifice this heir (Isaac). Through all these trials, Abraham had faith that God would indeed fulfil his promises.
In the NT the classical definition of faith is in Heb. 11: 1, which asserts that the believer in virtue of his faith holds to be true those realities which for the moment are invisible. The realities are, first, as in the OT, God the Creator of the universe (Heb. 11: 3) and secondly God the author of the OT covenant which is now realized in the salvation brought by Jesus, ‘the pioneer and perfecter of our faith’ (Heb. 12: 2).
So in the NT the object of faith is God revealed in Jesus Christ. Amongst Jews, faith in God is taken for granted (John 14: 1), but pagans must first believe in God (1 Thess. 1: 9) before they can accept the risen Christ, who reveals this God. It is the gospel of John which especially emphasizes that Jesus came from the Father to reveal him and make him known to humanity (John 1: 18). This is the substance of Peter's preaching after Pentecost (e.g. Acts 2: 36), and belief is followed up by baptism.
In the NT the profoundest exposition of faith is in the epistles of Paul, who shows that faith does not remain static; it grows (Phil. 1: 27; 2 Cor. 10: 15) and it issues in love, without which faith is empty. Faith is above all a confidence that the resurrection of Christ is an anticipation of a general resurrection at the End (1 Cor. 15: 14, 17; 2 Cor. 4: 14). Faith and baptism confer membership of the Body of Christ, which is both privileged and painful (Phil. 1: 29).
In Galatians and Romans Paul links his concept of faith to justification, and this is sometimes incorrectly understood. Paul taught that believers are justified (put right with God) not on the ground of faith but by Christ, in whom we have confidence and whose free grace justifies us. We are not justified by virtue of a subjective experience of conversion.
In the gospels, it is faith on the part either of sufferers or of members of their family (Matt. 8: 5–13) which enables Jesus to heal them. The father of an epileptic boy is assured that ‘all things can be done for the one who believes’ (Mark 9: 23), and the boy is cured. There are also accounts of healings without mention of faith (Mark 3: 5; 5: 7) because it was present in the human Jesus as Paul declares (Rom. 3: 22, 26, NRSV marg.) and invites us to grow in a like faith.