Paul makes it clear that faith absolutely is foundational to the Christian life. It is the means by which we lay hold of the promises we have in Christ. But what is faith exactly? What does it involve?
Genuine biblical faith is always a response to God. Faith is not some kind of feeling or attitude that humans one day decide to have because God requires it. On the contrary, true faith originates in a heart touched with a sense of gratitude and love for God’s goodness. That’s why when the Bible talks about faith, that faith always follows initiatives that God has taken. In the case of Abraham, for example, faith is his response to the amazing promises God makes to him (Gen. 15:5, 6), while in the New Testament Paul says that faith is ultimately rooted in our realization of what Christ did for us on the cross.
Many people define faith as “belief.” This definition is problematic, because in Greek the word for “faith” is simply the noun form of the verb “to believe.” To use one form to define the other is like saying “faith is to have faith.” It tells us nothing.
A careful examination of Scripture reveals that faith involves not only knowledge about God but a mental consent or acceptance of that knowledge. This is one reason why having an accurate picture of God is so important. Distorted ideas about the character of God actually can make it more difficult to have faith. But an intellectual assent to the gospel is not enough, for in that sense “even the demons believe.” True faith also affects the way a person lives. In Romans 1:5, Paul writes about the “obedience of faith.” Paul is not saying that obedience is the same as faith. He means true faith affects the whole of a person’s life, not just the mind. It involves commitment to our Lord and Savior Jesus Christ, as opposed to just a list of rules. Faith is as much what we do and how we live and in whom we trust, as it is what we believe.