What is the difference between custom and following the Prophet (peace and blessings be upon him), such as growing the beard and unbuttoning buttons, for example?

The questioner: His EminenceThe Shaykh : May Allah reward you and reward you with good, and may Allah benefit the Muslim community through you. What is the difference between custom and following the Prophet (peace and blessings be upon him), for example, growing the beard and unbuttoning buttons? And is Ibn 'Umar's (may Allah be pleased with him) following of the Prophet (peace and blessings be upon him) a matter of custom or a matter of worship?

The Shaykh : These questions are, in reality, of extreme precision, and it is no surprise that many students of knowledge overlook them, let alone others. Allah (Blessed and Exalted is He) said in the clear text of His Book: . By this noble verse, the Messenger (peace and blessings be upon him and his family) is the model for the Muslims, and he alone is the model, with no partner in this role. It is not permissible for a Muslim to take a model to follow and submit to, except the Prophet (peace and blessings be upon him and his family), as witnessed by the statement of (Blessed and Exalted is He): . This is a characteristic by which the Prophet (peace and blessings be upon him and his family) is distinguished from all other people, even the prophets who were sent before him. As he (peace and blessings be upon him) said when he saw the Torah in the hand of 'Umar ibn al-Khattab, reading from it. When he asked him about it, he said: "This is a page from the Torah... a brother of mine or a companion of mine." So he (peace and blessings be upon him) said: . The one worshipped is one, and He is Allah alone, with no partner for Him. The one followed is one, and he is Muhammad, the Messenger of Allah, with no equal for him. It is not permissible for anyone to take a follower and a model for himself after the Messenger of Allah (peace and blessings be upon him and his family), as stated in this hadith: .
But is this model absolute, encompassing everything the Messenger (peace and blessings be upon him and his family) did, even if it was from natural, ordinary personal matters or related to the environment in which he (peace and blessings be upon him) lived? An example of this is what came in the authentic collections that the Prophet (peace and blessings be upon him and his family) was served a meal one day containing a grilled snake (dhab). A woman from among his wives sent to him to tell him: "This is a dhab," because she knew from his nature (peace and blessings be upon him and his family) that he disliked this type of meat. When he was informed, the Prophet (peace and blessings be upon him and his family) stopped and did not join the people in eating this food. Khalid ibn al-Walid (may Allah be pleased with him) was in front of them, and he was eating with great appetite, until the broth was dripping on his beard. Our Prophet (may the prayers and peace of Allah be upon him) was looking at him with a look that had meaning. Khalid feared that this look from him was a look of disapproval, so Khalid said: "O Messenger of Allah, is it forbidden?" He said: . If Khalid desired what the Messenger (peace and blessings be upon him and his family) disliked from food, would he be contradicting the Sunnah? The answer is: No, because food, and what one desires and dislikes from it without prohibition, has no relation to the Shari'ah or worship. And the opposite is the opposite. The detailed discussion of this issue, and the adhan is being called, so it is best for us to listen now, and perhaps this is the conclusion, and we will depart, if Allah wills. You go to your mosque, and we continue our way as travelers, and praise be to Allah, Lord of the worlds.