If I had a post closing condition which was 30 day paystub after closing from my new job and it is less than what I was going to

That is a very generic question which really can't be answered. What kind of loan is it? How much lower is the pay? Do you still qualify ? Is the loan no longer salable on the secondary market? And finally what is the lenders stance based upon all that

I agree with the answer from Esta619. You would likely need to speak with the loan officer that was working with you to get the loan or call the new loan service company. However as a general rule of thumb - once a loan closes and FUNDS (meaning the money has been sent via bank wire to the Title Company to either pay off an existing loan or provide to the Seller in a purchase) the loan is complete. Anything following this (Ex; a job loss/change, credit change, asset increase/decrease) shouldn't affect any of the binding loan terms that have already been "consummated." So I expect you'll be OK, but be sure to follow the direction of your loan officer and/or the bank on this. This may not be the complete answer you were looking for, but I hope it helps!