Not
quite what I’m saying. I say that because the sentence is phrased as “because A, then B.” That’s simply not what I am saying.
Instead, what I am saying is that the possibility was there.
I’m basing it not on a theological or philosophical argument; but on what we read in the Gospel directly–ie the Temptation in the Desert. A temptation (by definition) isn’t possible unless the one being tempted can sin. We know He was tempted (else we say that the Gospel is fiction, and we certainly don’t go there).
What I am saying is that a temptation is not possible unless the one-being-tempted has at least the most remote possibility of actually giving-in to it.
See the Summa Q 41 A 1
http://www.newadvent.org/summa/4041.htm
Also, Hebrews 4:15
Christ gave us an example in the Gospel. An example of what? Of saying “no” to sin (of not-sinning). If one cannot sin, then neither can he be setting an example for others because we certainly can sin.
I have a coffee cup on my desk. It cannot sin. I don’t look at it and say “there’s an example of not-sinning.”
Of course, not, It cannot sin. If it cannot sin, it cannot set an example for me. In order to be an example, it has to have at least the possibility that it could sin.
So, again, if it were absolutely impossible (take those words in the strongest sense) for Christ to have sinned, then likewise, it would be impossible for Him to have set an example for us to follow.
Will we have the capacity to sin in heaven?
This might surprise you, but I’m going to say “I don’t know.”
First, the answer to your question might be divided into two categories: the present-day and after the Final Judgement.
As for after the Judgement, I will say “no.” (the fullness of heaven won’t happen until after the Judgement, but once that fullness does happen it will be absolute).
As for before then, we might expect the answer to be a definitive no,…
(aside: certainly, any theological discussion would lead to the conclusion “no.” I’m aware of that, so there’s no need to “prove” it. I take it as a given, believe me. Again, I take it as a given.)
… but then I think about Lucifer and the other fallen angels. Were they in heaven? Yes. Did they have the capacity to sin? Yes (we know they did, therefore they must have had the capacity). That means that it does not necessarily follow that “being in heaven” means “lacking the capacity to sin.” Therefore, I see an example, one that we can’t deny happened, that contradicts the theological answer.
That’s my response to your question, but I don’t see it going anywhere. Instead, I see it as one of those “how many angels can dance on the head of a pin?” questions.
Addition: by the way, there won’t be any sin in heaven. I don’t want anyone to think I’m trying to say there will be.