Musnad Abu Ya'la al-Mawsili 154:57

Abu Ya’la Ahmad ibn Ali ibn al-Muthanna al-Mawsili informed us, Abu Khaythama narrated to us, Jarir narrated to us, from ‘Ata’ ibn al-Sa’ib, from Ibn ‘Ubayd ibn ‘Umayr, from his father, that Ibn ‘Umar used to crowd at the two corners [the Black Stone and the Yemeni Corner]. I said, "O Abu ‘Abd al-Rahman, I have seen you crowding at the two corners in a way I have not seen anyone from the companions of the Messenger of Allah (may Allah bless him and grant him peace) crowd at them." He said, "If I do so, it is because I heard the Messenger of Allah (may Allah bless him and grant him peace) say: 'Touching them is an expiation for sins.' And I heard him say: 'Whoever circumambulates the House seven times and counts them, it is for him like the freeing of a slave.' And I heard him say: 'He does not place a foot nor lift another except that Allah removes a sin from him thereby, records a good deed for him thereby, and raises him a degree thereby.'"