Talmud Megilla 21a discusses two conflicting verses about how Moses acted when on Mt. Sinai. The verses are (the full verses are in the margin of the linked Talmud page, mentioned above):
Devarim 9:9 (My loose translation) "When I arose on the mountain to get the stone tablets of the covenant that G-d made with you. I sat in the mountain 40 days and 40 nights not eating or drinking."
Devarim 10:10 "And I stood in the mountain as during the first days - 40 days and 40 nights. G-d listened to me this time too and did not want to destroy you."
Rav resolves the conflict (one verse says "standing" and the other verse says "sitting") by stating that when one learnes something new, he should stand. When one reviews what he learns, he should sit.
My question - Rav's reasoning seems reversed if we understand the events of the two verses cited. In the first verse, where Moses mentions that he sat on the mountain, he was actually learning something new, as this was talking about receiving the first set of tablets. He was learning the laws the first time.
The 2nd verse, Moses was receiving the 2nd set of tablets, so, in a sense, he was reviewing what he already learned. There it says that he was standing.
How do we resolved how Rav learned (and said) his statements when the logic seems reversed?