Maisarah (may Allah have mercy on him) says that once I saw that Sayyiduna Ali (may Allah be pleased with him) drank water while standing. I said to him, "Are you drinking water while standing?" He replied, "If I have drunk water while standing, it is because I saw the Prophet (peace and blessings be upon him) do so, and if I have drunk while sitting, I have also seen him do it that way."