Yes he did, he urged passage of the Corwin amendment in his first inaugural address, and even went so far as to send letters with his signature to notify both the Northern and Southern states that the amendment passed congress.
“he urged passage of the Corwin amendment in his first inaugural address,”
Here is what Lincoln said about the Corwin amendment in his first inaugural address.
“I understand a proposed amendment to the Constitution—which amendment, however, I have not seen—has passed Congress, to the effect that the Federal Government shall never interfere with the domestic institutions of the States, including that of persons held to service ... holding such a provision to now be implied constitutional law, I have no objection to its being made express and irrevocable”
Doesn’t read to me that he “urged” anything vis-à-vis the Corwin Amendment.
Well....he was a little more cagey and weasel-like. He feigned ignorance and claimed he hadn’t actually seen the bill (an outright lie) and indicated he would support it. Of course as everybody at the time knew and as even his hagiographers today admit, Abe orchestrated the writing and passage of the Corwin Amendment.
This was entirely consistent with what he had always said. He was in favor of protecting southern slavery.