Ahmad ibn Muhammad from Musa ibn Al-Qasim from Ali ibn Ja'far from his brother (Imam) Musa ibn Ja'far عليه السلام, peace be upon them both, who said: I asked Imam عليه السلام about a man, is it permissible for him to lean against the wall of the mosque while praying, or to place his hand on the wall while standing without illness or weakness? Imam عليه السلام said: "There is no harm." And I asked Imam عليه السلام about a man who is in the obligatory prayer and stands during the first two rak'ahs, is it permissible for him to reach toward the side of the mosque and use it to help himself rise without weakness or illness? Imam عليه السلام said: "There is no harm in it."