Ibn Umar narrated from Bilal: "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"
SahihSahihHasan SahihBook 9 · Hadith 67
جامع الترمذي
Ibn Umar narrated from Bilal: "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"