Uriah needs 10 points or more, and you must raise Khaleb to Bond Level 1. Once you've done that, the scene will automatically trigger the next day, and Uriah will reach Bond Level 1 at the end. (The two don't even need to be in the tavern for that)
From that point on, you can go to the church on your day off. Once you've raised Uriah's points to 20 or more, simply go to the church, and the sex scene will trigger automatically.
Note: As soon as you increase a character's bond level, all points will reset to 0. Your 156 points will therefore disappear.
I hope I was able to help you solve your Problem =)
