Ahmad ibn Muhammad from Al-Hasan ibn Mahbub from Mu'awiyah ibn Wahb:
Abu Abdillah عليه السلام, peace be upon him, said: "The Messenger of Allah سبحانه وتعالى, may Allah سبحانه وتعالى bless him and his family, used to place the spear in front of him when he prayed."
Ali Akbar al-Ghaffari
Tahdhīb al-Aḥkām fī Sharḥ al-Muqniʿah, vol. 2, p. 346