I feel guilty most of the time and I usually cannot name what about. It is like background noise. Is that God convicting me or something else?

“Who can understand his errors? cleanse thou me from secret faults.”

David, in a psalm that moves from the sky to the law and then to his own heart, asks who can understand his errors and prays to be cleansed from hidden faults. Notice what he does not do. He does not try to excavate every one of them first. He hands the unknown material over to God rather than appointing himself the investigator of his own soul.

“How much more shall the blood of Christ, who through the eternal Spirit offered himself without spot to God, purge your conscience from dead works to serve the living God?”

The writer is addressing believers tempted to go back to the familiar temple system, and he contrasts sacrifices that cleaned the outside with one that purges the conscience. That word choice is deliberate. The target is not only the record kept in heaven but the accuser running inside your head. A conscience that will not quiet down is precisely what this passage says has been dealt with.