Here’s Sen. Ruben Diaz Sr. explaining to Erin Billups, of NY1, why he so vehemently opposed language in the revenue bill that recognized same-sex marriages performed outside the state in New York tax law.

It’s not what you think.

“It is insulting for the gay community,” the Bronx Democrat insisted. “It is insulting for us to tell them: We don’t recognize your marriage, we don’t want you to get married, we reject your marriage… but pay taxes.”

“It’s insulting. So why would I say: I don’t want you to get married, but as a married couple pay taxes. That’s hypocrisy. Pure hypocrisy…They cannot get married, they should not be paying taxes together.”

The same-sex marriage language appeared in Gov. David Paterson’s original budget proposal and the Assembly’s one-house budget resolution, but not the Senate’s.

It was removed from the two-way budget deal revenue bill that we now expect will come up for a vote very early Thursday morning (like, shortly after midnight), or, if saner heads prevail, sometime during the day.

Not long ago, I ran into Assemblyman Danny O’Donnell in the Senate hallway. He told me he has reintroduced an amended version of his bill, which is where this whole idea originated, to mirror the language in the governor’s budget.

The bill, which has no same-as in the Senate, won’t be live for passage until Friday. If it looks like the Legislature might leave town before then, O’Donnell said he will consider asking Paterson for a message of necessity.