He was only a servant (of Allah) receiving Commands from Him. He preached (the divine) message which he brought with him. He did not command anything to us (Banu Hashim) specially excluding other people except three points: he commanded us to perform ablution perfectly, and not to accept charity (sadaqah) and not to make pairing of donkey with horse.
In-book : Book 2, Hadith 418
English translation : Book 3, Hadith 807