Q:

Hebrews 6:18 - Impossibility for God?

In a discussion with a friend about the meaning of God's omnipotence, Hebrews 6:18 came up.  I have always understood this to mean that God literally cannot lie, but my friend understands it to mean that God will not lie.

Hebrews 6:18 (ESV)
so that by two unchangeable things, in which it is impossible for God to lie, we who have fled for refuge might have strong encouragement to hold fast to the hope set before us.

No English translation quite seems to bear a "will not" interpretation, as far as I can tell.  So, I am curious whether the Greek bears this. Would it be possible to render this alternately as something like "it is impossible that God would lie"?

A:

The sense of the verse would probably come out better if translated as it is not possible that God would be false.  The root of the Greek verb translated as lie (ψεύδομαι - pseudomai) is the noun ψεῦδος (pseudos), which one could translate as lie, but is probably better rendered as falsehood. 
The Concise Oxford English Dictionary (11th ed.) defines a "lie" as an intentionally false statement, but I think the emphasis here is not simply that God would never intentionally deceive, but rather that he would always remain steadfast in His promise.  Hebrews 6:18 is referring to what was just said in the preceding verse.  The two immutable things (KJV) were God's promise and His confirmation of the promise by an oath. Possibly Numbers 23:19 might have been called to mind:

God is not man, that he should lie, or a son of man, that he should repent. Has he said, and will he not do it? Or has he spoken, and will he not fulfill it?

In this sense, I would probably side with your friend.  It is not possible means that it won't ever happen: i.e. it's not possible that you will ever see it happen.

