The expression to get somebody out of a jam means to relieve for free someone from a bad or difficult situation. If somebody is in a jam they are in trouble or in a sticky situation. If you get somebody out of a jam you help them or prevent them from getting into further trouble.

1. I lent my friend £200 to help him get out of a jam. He's promised to pay me back as soon as he can.
2. My car has broken down. If you could come and pick me up you would really be helping me get out of a jam.

1. The boss would have fired me if you hadn't stood up for me. Thanks for getting me out of that jam!
2. I only got out of the jam I was in by asking some of my co-workers for advice. They really came through for me when I needed them!