English “on” in Romans 4:5 was translated from Greek preposition 1909 epi denoting superimposition. English “for” in Romans 4:5 was translated from Greek preposition 1519 eis denoting the point reached or entered into, of place, time, purpose, will or objective. Greek preposition 1519 eis appears immediately before English word “righteousness” in Romans 4:5 which was translated from Greek noun 1343 dikaiosune from a compound of Greek adjective 1342 dikaios describing and qualifying God’s definition of right and Greek suffix 4862 sun denoting union with God’s right. Romans 4:3 specifically refers to God performing the action of Greek verb 3049 logizomai unto Abraham whereby God instilled God’s right into Abraham, causing Abraham to be in union with God’s definition of right. Paul in Romans 4:5 is describing God’s generic process pursuant to God’s will and objective; which is the primary objective of the 4th chapter of Romans which was horribly mistranslated by human beings not chosen by God. We must always be cognizant of the fact that the bible tells us that Jesus came to divide “the rest” from God’s “seven thousand” “election” as biblically proved in previous posts. God’s word is designed to divide “the rest” from God’s “seven thousand” “election” as biblically proved in previous posts.
English “him that justifieth” in Romans 4:5 was translated from Greek verb 1344 dikaioo meaning to make right per God’s definition of right. Only God can perform the action of Greek verb 1344 dikaioo. Please remember the crux of God’s process pursuant to God’s will consists of God casting God’s word unto the earth and then either choosing or removing human beings from God’s process pursuant to God’s will as a predicate of human reaction to God’s word as biblically proved in previous posts.