In the Protestant tradition, faith is generally understood to be closely associated with ideas of belief, trust, and reliance. This understanding is founded in the doctrinal statements of the Reformers. One of their confessional statements explains: "the principle acts of saving faith are accepting, receiving, and resting upon Christ alone for justification, sanctification, and eternal life." The Reformers contrasted faith with human efforts to do good works as a means of justification. This understanding of saving faith has remained within the Protestant tradition. Saving faith is generally understood in terms of a belief of, trust in, and reliance on the person of Jesus and his work of atonement accomplished through his death on the cross.

In a more everyday sense, faith is often discussed in terms of believing God's promises, trusting in his faithfulness, and relying on God's character and faithfulness to act. Yet, many Protestants stress that genuine faith is also acted on, and thus it brings about different behaviour or action and does not consist merely of mental belief, trust or confidence or outright antinomianism. Hence, having authentic 'faith in Jesus' is generally understood to lead to changes in how one thinks and lives. However, the Protestant tradition holds that these changes in character and conduct do not have any value for obtaining a positive final judgment, but that a positive final judgment depends on faith alone