The noun faith corresponds to the verb believe. While in a few instances the noun is used for the content of what is believed (i.e., the faith, e.g., Acts 6:7), its primary usage is for the action of believing. The concept of faith is expressed in the OT primarily by the Hebrew word aman, whose root meaning denotes firmness or certainty. The particular verbal form of the word that is used suggests the acceptance of someone as trustworthy or dependable and a commitment and trust in the particular object of faith (e.g., Abraham believed God, Genesis 15:6). The primary NT word for faith carries the meanings "to believe," "to rely on," "to trust." Although faith can be bare intellectual assent (cf. James 2:14-16), the full sense of faith involves not only a knowledge of the object of faith (e.g., Romans 10:17) but the response of the whole person in trustful commitment in accordance with whom or what is believed. Related ideas of trust and reliance conveyed by other Hebrew and Greek words are also involved in the biblical concept of faith. (See also HOPE, TRUST).
This topic is from the Lockman Foundation.