If you bring it to their attention they may deny the loan, unless based on the banks qualifying criteria you make enough income alone to qualify by yourself. Even if you do not tell your mortgage banker, they will probably discover it before the closing and then the fact that you did not tell them will raise even more of a red flag thus lessening the chances of you getting the mortgage.
If you do not get the loan, a normal contract of sale has a mortgage contingency stating that if you do not get the loan through no fault of your own (such as job loss), the deal would falter and you would get back your down payment.
Your spouse should make it top priority to find another job, that may be more of a concern than losing the deal (unless you got a true dream deal). Be careful and make sure you will be able to make the payments even if the bank is willing to still give you the loan! Oh, and unemployment is not counted as income in the eyes of a bank.
If I can be of further assistance, please let me know. Good luck!
Mitchell S. Feldman
Associate Broker/ Director of Sales
Madison Estates & Properties, Inc.
Office: (718) 645-1665/ Cell: (917) 805-0783
Sterling National Bank
With loans these days they generally do a re-check on employment before settlement (7 days) and will likely find this out. If you wait for them to find out there may be repercussions. You should alert your lender immediately to see if you still qualify for the same loan or any loan. And then you should alert your buyers agent so they can prepare if you need to withdraw from the contract.
best of luck.