Examples of the Sunnah that is good by Shari'ah, not by ijtihad or rational istihsan.

The Shaykh : I will give you some examples to clarify this important reality. For instance, we all likely know that when the Messenger (peace and blessings be upon him) conquered Khaybar, he made a treaty with the Jews on certain conditions. One of those conditions was that he gave them Khaybar to work it as tenant farmers, with half the produce belonging to them and the other half belonging to the Messenger (peace be upon him) and his Companions. Among the conditions he imposed on them, he said to them (peace and blessings be upon him): ; meaning, you know that Khaybar was conquered by force of the sword and that...
...and its people and inhabitants became slaves to the Messenger (peace be upon him); that is, captives. However, the Messenger (peace be upon him) saw it in the interest of the Muslims at that time for Khaybar to remain in the hands of the Jews, who would farm it and cultivate it for the Muslims, with half for them and the other half for the Jews. But he said to them: ; meaning, for the period we deem appropriate. Then the Messenger of Allah (peace and blessings be upon him) passed away, and the Jews were still in Khaybar. Abu Bakr came after him and passed away while they were still there. Then 'Umar came, and they were still there, until it occurred to 'Umar to expel them from Khaybar. He gave them notice and ordered them to carry whatever light luggage they could, because they had been conditioned to remain as long as they wished. It occurred to the Caliph, the successor of the Messenger (peace and blessings be upon him), to expel them from Khaybar.
This is the example that clarifies for you the good Sunnah in the first correct meaning, and the good bid'ah (religious innovation) in the interpretation of the group when they see the word "good." We say: There is no doubt that 'Umar did something the Messenger (peace be upon him) did not do; he expelled the Jews from Khaybar, whereas the Messenger (peace be upon him) had left them there and died while they were still there. Likewise, Abu Bakr, after the Messenger (peace and blessings be upon him), did not expel them from it. So 'Umar's expulsion of the Jews is a new matter, and there is no doubt or ambiguity about that. What is the ruling on this matter? Do we call it a bid'ah? We say: No. As for them, they call it a bid'ah and describe it as a good bid'ah. We say: There is no harm, as long as the evidence is established for the Shari'ah legitimacy of 'Umar's action, then it is not—in our terminology—a bid'ah, but rather in your terminology it is a bid'ah. In our terminology, it is not a bid'ah; because 'Umar executed an order from the orders of the Messenger (peace be upon him). First, this is in the explicit statement of his (peace be upon him): . Second, note the previous condition: . The will of the Muslims ended, so they expelled them from Khaybar. Therefore, 'Umar did not innovate a matter in the religion, but rather executed a previous order from the Messenger (peace and blessings be upon him), which is his saying: . We do not allow ourselves to say that 'Umar innovated in the religion of Allah something that was not from Him. As for those who speak of good and bad bid'ah, they say, even if only in words, that 'Umar innovated; what? He expelled the Jews from Khaybar, but this is a good bid'ah. Perhaps the previous answer does not occur to their minds, that he executed an order issued by the Messenger (peace be upon him). But they bring the general evidence: to the end of the hadith.
So we say at that time: The disagreement between us and them remains if they note this description of "good," a good Sunnah, and that the "good" is not what people consider good in their minds, but rather what the Shari'ah evidence has established as good. At that time, the disagreement between us and them remains a verbal disagreement. This is a reality we must know and must take as a path to bring the dissenters to this Shari'ah reality; because we are not concerned with the words as much as we are concerned with the meanings that were poured and cast into these words. If they agree with us that there is a good bid'ah in Islam, and that the "good" is known by the way of Islam, then let them call it whatever they wish. But we consider it beneath us to call 'Umar's execution of a noble Prophetic order a bid'ah. This is an example.
Another example, and this is what the majority of these people who hold that there is a good bid'ah in Islam cite as evidence. They say: The gathering of the Qur'an by the Companions. Our position toward this matter is exactly the same as our position toward 'Umar's expulsion of the Jews from Khaybar. We say, with the strongest condemnation: Is the gathering of the Qur'an a bid'ah? May Allah protect us from such talk! Because whatever the description of this obligatory matter, for which indications in the Noble Qur'an and the Sunnah have established the necessity of preserving the Qur'an, such as His saying (Glorified and Exalted is He): , here is an indication that there is a Book; that is, this will be a Book. And as his (peace and blessings be upon him) saying: . So any means that achieves this goal which our Lord (Mighty and Majestic) commanded in the Qur'an and His Prophet (peace and blessings be upon him) in the Sunnah is an obligatory means to adopt. Therefore, the scholars and jurists say: Everything without which the obligatory cannot be established is itself obligatory.
So the gathering of the Qur'an, especially when it was exposed to loss due to the loss of its carriers, is one of the most obligatory duties; because if they had not done so, Islam would have been lost, and the religion of Islam would have become like Judaism and Christianity, with no peak and no bridle, having no reference. If one of them wanted to know a word spoken by Moses or spoken by 'Isa (peace be upon them both), that would have been an impossible matter. If it were not for the Companions hastening to gather the Qur'an, their Book would have suffered what the Gospel and the Torah suffered. Therefore, in reality, they did what 'Umar did later; they performed a duty required by the evidence of the Shari'ah. So did he innovate a bid'ah?! We disavow, as we said, calling their action a bid'ah. But we say: He performed a duty for which the cause to achieve it had not arisen in the time of the Messenger (peace be upon him). Therefore, in the same hadith, there is an explanation of the cause requiring the gathering of the Qur'an, which is his saying: When the killing intensified among the reciters of al-Yamamah (that is, it became severe among them), and seventy reciters were killed in one day. 'Umar came to present to Abu Bakr al-Siddiq the gathering of the Qur'an, and they agreed on it. Then they brought Zayd ibn Thabit and presented it to him, and they did not stop until he was convinced. Here is a profound wisdom, but unfortunately, it does not suffice; the profound wisdom is that the gathering of the Qur'an, which is the foundation of the Qur'an, because it was not in the time of the Messenger (peace and blessings be upon him), when he tasked Zayd ibn Thabit to carry out the gathering of the Qur'an, he said to them: How do you do or make something that the Messenger of Allah (peace and blessings be upon him) did not do?
Look at the difference between the Companions who understood the danger of innovation in the religion; how they feared that if they gathered the Qur'an, they would have introduced something abhorrent into Islam. Whereas you find today the most ignorant ignorant and the most knowledgeable scholar, if told to him: Do not do such and such; he will say to you: My brother, what is the problem? It is nothing but the remembrance of Allah and sending blessings upon the Messenger (peace be upon him). Fine; what is the problem with gathering the Qur'an? It is the preservation of the entire Shari'ah. They were very, very cautious about innovation in the religion, to the point that they might leave something that is predominantly a prescribed Sunnah, fearing that they would innovate in Islam something that was not from the Sunnah.
So, for example, Abdullah ibn 'Umar ibn al-Khattab called the Dhuha prayer a religious innovation. This forced the scholars, in light of the many explicit texts regarding the prescription of the Dhuha prayer based on the actions and words of the Messenger of Allah (peace and blessings be upon him), to say: Perhaps he meant the Dhuha prayer in the mosque, the Dhuha prayer in the mosque; because this prayer took on a character that did not exist in the time of the Messenger (peace and blessings be upon him). This is because the default for voluntary prayers is that they are performed in the homes, as he (peace and blessings be upon him) said: . So look at the difference between the Salaf and the Khalaf. The Salaf were scrupulous about collecting the Qur'an for fear of introducing innovation into the religion, while the Khalaf innovate whatever their souls and desires wish. And the answer is prepared; what is in it? It is the remembrance of Allah and sending blessings upon the Messenger (peace and blessings be upon him)!!
There is something very serious in it; and that is presuming upon Allah and getting ahead of the Messenger of Allah, who is the one who conveys from Allah. So if you say: This is a good innovation, even if the Messenger did not do it, even if the Companions did not do it, even if the four Imams did not do it; it means that you are legislating something from yourself and ignoring the conclusive proofs that this thing is an introduction into the religion and misguidance. Therefore, the collection of the Qur'an by the Companions is not a religious innovation, but rather it is an obligatory matter that 'Umar and Abu Bakr al-Siddiq carried out, and the scribe of the revelation of the Messenger (peace and blessings be upon him), Zayd ibn Thabit, followed them in that, and the Companions agreed upon it because they saw that it was among the necessities of the religion.