I will use human argument here, as human logic is what this debate comes down to (because the Word is clear on the subject)
I do understand what Jason means by "internal temptation" (even though it is not a Biblical theory),
but internal temptation comes from setting ones own maxims beyond what one deems moral,
and then needing to reset those maxims (which is where we all fail, when we recognize a sin, yet do it)
Jesus NEVER let his maxims (self limits) exceed His morals, and His morals were pure, therefore He remained pure.
So in this sense, the temptation was not to RETURN to a known sin ("known" is used in the Biblical, intimate sense. As in prior experience), but to explore another possible path.
Temptation is when we are presented with an option that extends beyond our morals (which all men have been given through the knowledge of good and evil), and yet seems beneficial (at least short term). For the rest of us, temptation is often within the bounds of our maxims, yet outside the bounds of our morals, which makes it TEMPTING because we have done similar things in the past, even though our conscience currently says NO!
For Christ, temptation was beyond both His morals AND His maxims, as He had never set His maxims beyond His morals. We experience this when we say "but I would NEVER do THAT",
except sometimes we do.
Christ certainly saw the benefits of Satan's temptations, but did not fall prey to them. If He never saw benefits in them, they would not have been temptations at all.
Do you know what Satan offered?
A way out.
He offered Christ a free pass of the Cross to obtain the prophecies Kingdom.
Why go through death, when I can just hand you all of it?
As in, I'll concede if you concede in just this one little thing.
But our Saviour resisted!
When Satan offers you a free pass at obtaining your goal, do you concede for what is readily available,
or do you wait upon the Lord?
Look at the prosperity teachers. Did they concede?
Look within ourselves. Have we conceded?
Yes.
But Christ did not.
It was a struggle, but a Holy struggle, and a pure and Glorious victory.
Remember, the spotless lamb still needs to be a lamb.
It can't be a spotless replica of a lamb. That has no value.
Christ has infinite value.
(Long post. Sorry guys. If I had time, I could probably have come up with a way to sum it all up in 3 sentences. Please respond with any questions about maxims vs morals in a pm, as it will derail the thread)