“Now faith is the substance of things hoped for, the assurance of things unseen” (Heb 11:1). Hebrews 11:1 does not provide a formal definition of faith. But, as far as descriptions of faith go, one cannot do much better.
Expressed in formal terms, faith is an act whereby person A trusts person B regarding some object C. To appreciate this definition, let’s break it down into its three basic components.
1. A trusts. A is the person who exercises faith.
2. A trusts B. Faith is not an act of self-reliance. In exercising faith, person A relies on person B.
Person A trusts person B due to person B’s perceived trustworthiness. That trustworthiness includes at least three dimensions. Person A is persuaded (a) that person B is intellectually credible (i.e., that person B knowns what he is talking about), (b) that person B is volitionally committed to person A’s good (i.e., that person B has no reason to harm or deceive person A), and (c) that person B is virtually able to perform what is claimed or promised (i.e., that person B is someone capable of having done what he said he did or of doing what he says he will do). With respect to the latter, it is not uncommon, for example, for children to doubt that their fathers were ever capable of accomplishing the feats they claim to have accomplished in their younger days.
3. A trusts B regarding C. C is what A trusts B about. C may be theoretical. In such a case, A is persuaded by B that something is true. Formally expressed, A trusts B that C (“that C” = some truth regarding what is). Or C may be practical. In such a case, A is confident in B that something is to be done. Formally expressed, A trusts B for C (“for C” = some good that is to be performed).
When C is theoretical (A trusting B that C), faith is opposed to sight. Rather than trusting A’s own cognitive capacities, A trusts B’s cognitive capacities. When C is practical (A trusting B for C), faith is opposed to works. Rather than trusting A’s own ability to do something, A trusts B’s ability to do something.
In saving faith, the believer trusts God regarding both theoretical (A trusts B that C) and practical objects (A trusts B for C). Based on the credibility of God’s testimony, the believer trusts God that God exists (Heb 11:6), that God created all things (Heb 11:3), that God raised Jesus from the dead (Rom 10:9), etc. (NB: each of these objects of faith, in turn, reinforce the credibility of God: because we believe that God is, we believe that God is able to create all things, because we believe that God created all things, we believe that God is able to raise the dead, etc. [cf. Rom 4:17]). However, saving faith involves more than trusting God regarding theoretical objects. The demons believe, in this sense, and shudder (James 2:19). In saving faith, the believer also trusts God that he will do certain things: that God in Christ will be rich in mercy to all who call on him (Rom 10:12), that God in Christ will reward everyone who seeks him (Heb 11:6), ultimately, that God in Christ will be the believer’s God and redeemer and that the believer, in turn, will belong to God as one of his redeemed people (Ps 31:14). Resting on the credibility of God’s promise to us in Christ, saving faith is the means whereby we receive God in Christ along with all the blessings that God has promised believers in Christ (John 1:12). In saving faith, God is both the one on whose credibility we rely and the promised good that we receive.
Saving faith, thus described, is “the substance of things hoped for” and “the assurance of things unseen” (Heb 11:1). As “the substance of things hoped for,” faith is the basis of our hope for good things. Faith grounds or “sub-stands” our hope. As “the assurance of things unseen,” faith is also the means of being assured of things we could not otherwise know on the basis of our own sense perception. By faith, we may be assured of invisible things on the basis of God’s testimony (Heb 6:16-18).
