The Driller Killer (1979) on Netflix

New York City. Reno Miller, a scruffy young artist, enters a small Catholic church in Spanish Harlem where he walks to the front where an elderly bearded man is kneeling and chanting "pity the sinners" over and over. Reno seems to recognize the man as his long-lost father, whom is now apparently a derelict. The old man unclasps a hand and grabs Reno's hand. Reno runs, grabs his girlfriend Carol, who accompanied him to the church, and leaves. They ride in a taxi towards downtown, and Reno calls the man a "degenerate" and a "bum". Evidently, the derelict had a piece of paper with Reno's name and phone number and requested a meeting at the church to talk to him. Reno, despite knowing that the derelict was his father, denies knowing him to Carol. Reno and Carol go to pick up Pamela, their other roommate, who is in a local bar watching a punk rock band perform.