What some pilgrims do when they finish the Farewell Tawaf, i.e. not turning their backs towards the Ka`bah; rather, walking backwards with their faces towards it until they exit the mosque, is not part of the Sunnah; rather it is a reprehensible innovation. This is what some people do, claiming to venerate the Ka`bah by doing so. If this were really a sign of respect for the Ka`bah, you would find that the Prophet (peace and blessings be upon him) and the Companions had done that, but there are no reports to that effect.
Sheikh Abdul-`Aziz ibn Baz, the late Mufti of Saudi Arabia, stated: “When the pilgrim has finished bidding Farewell to the House and wants to leave the mosque, he should walk normally facing forward until he leaves. He should not walk backward because there is no report that the Prophet (peace and blessings be upon him) or his Companions did this; rather, it is a bid`ah innovation (in religion). The Prophet (peace and blessings be upon him) said, ‘Whoever does any action that is not part of this matter of ours (Islam) will have it rejected’ (Muslim). And he (peace and blessings be upon him) said, ‘Beware of newly-invented matters [in religion], for every newly-invented matter is an innovation and every innovation is a going astray’ (Abu Dawud). We ask Allah to make us steadfast in adhering to His religion, and to keep us safe from anything that goes against it, for He is the Most Generous, the Most Kind.”
The late Sheikh Ibn `Uthaymeen, a prominent Saudi Muslim scholar (may Allah shower mercy on his soul), said when listing the mistakes that some people make during the Farewell Tawaf: “Some people, when they perform the Farewell Tawaf and want to leave the Mosque, walk backwards saying that they do not want to turn their backs on the Ka`bah. This is a bid`ah (innovation in religion) that was not done by the Messenger of Allah (peace and blessings be upon him) or by any of his Companions. The Messenger of Allah (peace and blessings be upon him) venerated Allah and His House, and, if this were indeed an act of veneration towards Allah and His House, the Prophet (peace and blessings be upon him) would have done it. The sunnah is to leave the mosque walking forwards, even if one turns one’s back towards the Ka`bah in doing so.