Clarifying the criterion between customary Sunnah and devotional Sunnah

The Shaykh : As we said regarding the Sunnahs, the customary Sunnahs: if you wish, you may do it; if you wish, you may not. Hajj is not a customary Sunnah at all. I mentioned an example in answer to your question: what is the criterion, what is the rule for distinguishing the devotional Sunnah from the customary Sunnah? I told you that when the Messenger (peace and blessings be upon him) urges something from the customary Sunnahs, it exits the category of customary and enters the category of devotional. I gave you the example of wearing white clothing The strongest example for your question is the beard, because as I said, the Arabs used to grow beards; it was an Arab custom. In contrast to that, the Zoroastrians and the Christians used to grow beards. Perhaps you read the book *Fiqh al-Sirah* by al-Bouti, which I mentioned in the previous session, where a man from the Zoroastrians came to the Prophet (peace and blessings be upon him) as an envoy from Kisra. He came, what? With a beard. He said to him: He said: My Lord. Meaning Kisra. He said: So, since the Zoroastrians, and still are, have the custom of shaving the beard, I said that I gave the example of wearing white clothing as the strongest example for what we are discussing now, because it was the custom of the Arabs to grow the beard. So the Prophet (peace and blessings be upon him) first approved them. If that were all, I would agree with those who say it is a custom: whoever wishes may do it, and whoever wishes may leave it. No. Because first, he commanded it with a command of obligation, as we agreed, and then he made it part of the fitrah (the innate natural disposition) that does not accept change or alteration as long as there is a Muslim on the face of the earth...