It is narrated from Hazrat Abu Saeed Khudri (may Allah be pleased with him) that once Hazrat Abu Musa Ash'ari (may Allah be pleased with him) greeted Hazrat Umar (may Allah be pleased with him) three times. He was not granted permission, so he returned. Later, when Hazrat Umar (may Allah be pleased with him) met him, he asked, "Why did you leave?" He replied, "I sought permission three times. When I was not granted permission, I left. We have been commanded to do so." Hazrat Umar (may Allah be pleased with him) said, "Present a witness for this, otherwise I will punish you." Hazrat Abu Musa (may Allah be pleased with him) went to a gathering of the Ansar. They said, "Even the youngest among us can bear witness to this." Thus, Hazrat Abu Saeed Khudri (may Allah be pleased with him) went with them and bore witness to it, so Hazrat Umar (may Allah be pleased with him) let him go.