"Abdullah, may Allah be pleased with him, said: "I have not failed to touch these two corners since I saw the Messenger of Allah touching them, the Yemeni Corner and Black Stone, either when it is difficult or when it is easy.'"
Sunan an-Nasa'i Book 24, Hadith 335
← Previous Hadith "The Messenger of Allah did not touch any of the corner of the House except the Black Corner and the one that is next to it, in the direction of the houses of Al-Jumahiyyain."

Sunan an-Nasa'i Book 24, Hadith 334 Next Hadith → "Since I saw the Messenger of Allah touch it, I did not fail to touching the Stone whether it was easy or difficult."

Sunan an-Nasa'i Book 24, Hadith 336