Saw his man Stan with the blunt in his hand
(Ah sh...) You know the transaction

from A Tribe Called Quest – Midnight Lyrics on Rap Genius

Meaning

He saw his friend about take a puff of the blunt, but since the only curse word Q-Tip uses in this sing is ‘nigga’(which was a little lighter back then with music.) he keeps from saying any other curse words by stopping the audience from going ‘Aaaaw shit!'
And doesn’t say 'fuck’ because…

You know the transaction

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