Sahih Muslim 1333j

A'isha (Allah be pleased with her) reported:I asked Allah's Messenger (ﷺ) about the wall, circumpassing the House (i. e. whether the wall on the side of Hijr was included in the Ka'ba). He said, Yes. I said: Then why did they not include it in the House? He said: 'Your people ran short of the means (to do so). I said: Why is it that the level of its door is raised high? He said: Your people did it so that they should admit one whom they liked, and forbid him whom they disliked, and if your people were not new converts to faith, and I did not apprehend that their hearts would feel agitated at this. I would have definitely included (the area of) this wall-in the House and would have brought the door to the level of the ground