From him, from Abu Jamilah, from ‘Ala’, from Muhammad ibn Muslim, from one of the two (Imams عليه السلام), peace be upon them:
Imam عليه السلام said: "The obligatory prayer is not valid inside the Ka‘bah."
Ali Akbar al-Ghaffari
Tahdhīb al-Aḥkām fī Sharḥ al-Muqniʿah, vol. 2, p. 413