This point is strengthened by the fact that Allah (awj)...

This point is strengthened by the fact that Allah (awj) taught Adam (ع) all the “names” and it was only he that knew them and not even the angels had that knowledge. On that account, Adam (ع) was appointed teacher to the angels, bestowing to them the knowledge of the “names”. All these incidents were prior to Adam’s (ع) eating from the forbidden tree. Hence, it can be inferred that Adam (ع) was in fact a prophet when he committed the deed in question.

The problem is that according to the Shi’a school of thought, prophets are absolutely infallible and are even free of minor sins. Thus, the prohibition must be interpreted as an advisory warning and so Adam’s (ع) guilt was neglecting that which was more meritorious. But since prophets are at a high station of Divine knowledge, they are guilty…