Understanding this verse is essential to deriving the most from this chapter. It establishes a good, practical definition of faith, but it is not the only one, since the Bible uses the term "faith" in several other ways. We have to be thinking as we read, or we may get an idea about faith other than the one God intends within a given context.
Galatians 1:23 uses "faith" in a somewhat different manner. "He who formerly persecuted us now preaches the faith which he once tried to destroy." In context with "preaching," faith, as used in religious parlance, means "a confession," thus "a creed," "a body of religious beliefs," or "a statement of the principles of one's way of life." The New Testament often uses "faith" in this manner. Its usage in Jude 3 is similar but a bit clearer, as a body of beliefs to which we must cling steadfastly and apply to life's challenges.
In John 20:29, the apostle relates, "Jesus said to him, 'Thomas, because you have seen Me, you have believed. Blessed are those who have not seen and yet have believed.'" Here, with Jesus Christ as faith's object, believing indicates a personal trust or confidence in Him. Paul, in Romans 3:22, puts it in a different light: ". . . even the righteousness of God, through faith in Jesus Christ, to all and on all who believe." Here, in a legal context, it indicates a level of personal confidence or trust in what Christ did as a means of justification and therefore access to God.
Romans 10:17 imparts vital understanding on how faith in God becomes part of our thinking and conduct: "So then faith comes by hearing, and hearing by the word of God." Faith becomes an element of our thinking by our hearing words that concern the objects of faith: our Father in heaven; His Son, Jesus Christ; and Their message, the gospel of the Kingdom of God. Interestingly, Paul emphasizes hearing rather then merely reading, though reading is included in the sense of hearing. Jesus declares in John 6:63, "The words that I speak to you are spirit, and they are life." Hearing—or more correctly, listening—is probably Jesus' most frequent and consistent exhortation during His ministry.
If we do not listen thoughtfully, we will not have faith in the right object. Regardless of the context, faith always contains a mixture of believing, knowing, understanding, trusting, and sometimes even bold conviction—all locked together and pointed toward a specific object. Within the Bible, that object is almost always either God, Jesus Christ, the Word of God, or a messenger sent by God, whether angel, prophet, or minister.