"The Prophet left me while he had a joyous look of contentment and he returned to me grieving. So I asked him about that and he said: 'I entered the Ka'bah, and I wished that I had not done it. I fear that my Ummah will follow me (in that) after me.'"
Jami` at-Tirmidhi Book 9, Hadith 66
← Previous Hadith (Another chain) and they said: "Zaid bin Yuthai" and this is more correct.

Jami` at-Tirmidhi Book 9, Hadith 65 Next Hadith → "The Prophet performed Salat in the interior of the Ka'bah." And Ibn Abbas said: "He did not perform Salat in it, but he said the Takbir."

Jami` at-Tirmidhi Book 9, Hadith 67