Jesus frequently denounced the scribes and the Pharisees and their destructive traditions, for He was not only concerned about them but those who would follow their heresies. Since Jesus “knew all men, and had no need that anyone should testify of man, for He knew what was in man” (John 2:24-25), Jesus was well aware of the hearts and the motives of these “super-religious” individuals in His day (or, at least, those who appeared to be “super-religious”).
Jesus called them out in Matthew 23, saying many things to their detriment and exposing their self-serving motivation—“all their works they do to be seen by men” (23:5). The scribes and the Pharisees never gave a second-thought (apparently) to the fact that all their works were seen by God in heaven. All they were concerned about was making sure that man saw their good deeds. If they were not going to get any attention or any credit, then they were unlikely to act.
Think about your motivation for your good deeds. What if no one ever knows?