Musnad Ahmad 2148

It was narrated from Ibn 'Abbas (رضي الله عنه) that he said: The Prophet (ﷺ) entered ihram for Hajj, and when he arrived [in Makkah] he circumambulated the House, and went between as-Safa and al-Marwah, but he did not cut his hair or exit ihram, because he had the sacrificial animal with him. He told those who had not brought sacrificial animals with them to circumambulate the House and go between as-Safa and al-Marwah, and to cut their hair or shave their heads, then exit ihram.