In the Scriptures, justification has both eyes on the future. Anyone who has ever read Paul knows that Abraham believed God and it was counted unto him as righteousness (Genesis 15:6). But what was it that Abraham believed? What was the promise upon which his faith hinged? If we are to take the argument of Paul (and Genesis) seriously we are left with a short list of possibilities. So short, in fact, that there is only one promise on it: “So shall your descendants be” (Genesis 15:5).
This raises the question, “Just how shall his descendants be?” Thankfully, the promise comes stocked with a picture: “Look toward the heavens and recount the stars, if you are able to recount them” (v. 5). Survey the heavens. See their number. See their narrative. This is the promise of God.
There is a correspondence between the multiplicity of the stars in the heavens and Abraham’s seed. If we take this seriously we have to wonder whether many of those who insist on justification by faith really believe what Abraham believed. Do they believe that the seed of Abraham will be easily tabulated on the last day? Or do they believe, as Abraham did, that counting will be a useless gesture when his sons go marching in? If they don’t believe the latter how can they be said to share the faith of Abraham? Theirs is an unjustified belief. It is very ironic that many who defend justification by faith have trouble believing the very promise which justified their father Abraham—whose seed they are!