Lender relists for profit in Texas. Can he keep the profit?

[Mac Bradley]

Lender is high bidder at auction and bids minimum bid so no money is
owed to Borrower. Lender then lists the property for sale w/ a real
estate agent and property sells at a profit over the original auction
bid. Can the lender keep the profit or does he have to refund that
profit back to the original borrower?