The Bonnies (10-6, 3-2 Atlantic 10) scored their last 10 points from the foul line, going 8 for 8 in the final minute.
Isaiah Miles drained a 3-pointer to pull the Hawks (7-9, 1-4) within 55-54 with 5:41 left and hit again at 2:29 to make it a one possession game. Jaylen Adams countered with two free throws and then the Hawks missed three shots and had a turnover in three possessions, setting the stage for the parade to the foul line.
DeAndre Bembry had a career-high 27 points for Saint Joseph's, hitting 6 of 9 3-pointers.
St. Bonaventure finished 13 of 17 from the foul line after going 1 of 2 in the first half, when Saint Joseph's led 29-28 at the break.