Using the phrase "peace be upon him" for anyone other than the Messenger ﷺ

Q: While reviewing the topics in the book *Uqd al-Durar fi Akhbar al-Muntadhir*, I found some narrations attributed to 'Ali ibn Abi Talib (may Allah be pleased with him) phrased as follows: It was narrated from 'Ali ibn Abi Talib (may Allah be pleased with him) that he said: The Messenger of Allah ﷺ said: "A man from my household will emerge under nine banners." What is the ruling on using this phrase, meaning (may Allah be pleased with him) or something similar, for anyone other than the Messenger ﷺ?

A: It is not appropriate to single out 'Ali (may Allah be pleased with him) with this phrase. Rather, it is prescribed to say in his case and the case of the other Companions (may Allah be pleased with them) or "may Allah have mercy on them," because there is no evidence for singling him out with it. The same applies to some people saying "may Allah honor his face," for there is no evidence for that and no reason to single him out with it. It is better to treat him like the other Rightly Guided Caliphs, and not to distinguish him from them with any phrases that have no evidence.