From faith to faith?
Paul, in referring to the good news, wrote in Romans 1:17:
"For therein is the righteousness of God revealed from faith to faith: as it is written, The just shall live by faith."
or, at least this is the English language version we have been left with (KJV). But, this translation presents a delima. The phrase, "from faith to faith," is utterly meaningless in our normal way of speaking and therefore is a source of great confusion.
The Greek versions of the phrase which has been translated "from faith to faith" say:
"ek pisteos eis pistin."The Greek preposition "ek" means "from" or "out of," or "of." Simple enough.
However, the Greek preposition "eis" means "for" and is used to indicate the object, aim, or purpose of an action. The action in this instance is in the verb "revealed" (apokaluptetai - to uncover). So, the object, aim, or purpose of uncovering the righteousness of God is "eis pistin," "for [the purpose of] faithfulness." Compare the use of "eis" in Matthew 26:28, Acts 2:38, John 20:30, and Romans 10:17. God's faithfulness is revealed for the sake of ours.
To reinforce the one-way driving force of God's faithfulness, later, in Romans 3:3-4, Paul writes:
"For what if some are unfaithful? Will their unfaithfulness cancel the faithulness of God? Let it not be!
A better translation of Romans 1:17 is:
"...for in it (the "good news") is reveled out of faithfulness, the uprightness of God for the sake of faithfulness; even as it has been written, "But, the upright lives by his faith." Hab. 2:4
What Paul is saying in Romans 1:17 is: The "good news" (of the Messiah) reveals God's uprightness. This revelation is demonstrated through God's faithfulness. The stated purpose of the revelation of God's uprightness is to produce a faithful response in those who heed the good news.