It was narrated from Ibn 'Abbas that: The Prophet ﷺ said: "I have been commanded to prostrate on seven bones: on the forehead"- and he pointed with his hand- "on the nose, the hands, the knees and the ends of the feet".
The Prophet Muhammad (peace be upon him) taught us how to perform salat correctly so that we can gain maximum benefit from it both spiritually and physically. He showed us how important it is for us to be humble before Allah by prostrating on these seven bones during prayer time. By doing this regularly with sincerity and devotion we can strengthen our relationship with Allah and become closer to Him through prayer.