The principle of usul al-fiqh (the principles of jurisprudence) states: The default ruling for commands and prohibitions is obligation and prohibition, unless there is a factor that shifts them to recommendation or dislike.

The student : After Maghrib, O Shaykh, we were discussing a matter in usul al-fiqh (the principles of jurisprudence) with some of the brothers, and I asked a group of scholars about it. It is the matter that the correct view among the usuliyyin (specialists in principles of jurisprudence) is "that a command is for obligation, and a prohibition is for prohibition, unless a sign or a shifting factor comes."

The Shaykh: Perfect.
The student : There are, O Shaykh, dozens of commands and dozens of prohibitions that they have made into matters of recommendation and dislike without a shifting factor. The question, O Shaykh, is: Why did they establish this principle and shift it, when this principle must be based on a statement, an action, or an estimation from reality?

The Shaykh : It is, of course, from tracking, meaning a principle is established and derived from the scholars' tracking of the individual words of hadiths, verses, and rulings. But the truth is that the statement that the default ruling for a command is obligation cannot be the basis for people's practice, and departing from this principle requires a sign. However, something applies here: some may observe a sign and others may not observe it; this may happen. But because such a disagreement occurs between two imams, or two scholars, or two students of knowledge, this should not lead us to invalidate the basic principle, which is: "The default ruling for a command is obligation."
The student : We, O Shaykh, do not invalidate it, but we say the criterion. For example, O Shaykh, we studied in the college, when the teachers mentioned this principle, they mentioned seven examples, among them the hadith: , and witnessing in sales, and writing in sales. They say some went in the majority to obligation, and others differed and said it is for recommendation. So we say: What is the sign or the shifting factor for those who say it is for recommendation?

The Shaykh : Every text must be studied on its own, and this is asked of the one who adopts that the command in these examples is not for obligation. As for , there is nothing that shifts the command for the able person to recommendation rather than obligation. As for witnessing, the Companions dealt with each other, and the Messenger of Allah (peace and blessings be upon him) dealt without doubt; this is practical evidence that the command is not for obligation. As I said earlier regarding the fact that if, for example, an action comes after a prohibition, the prohibition can be interpreted as for discouragement, or if we say now that an action comes after a command, the command can be interpreted as not being for obligation. So the practice of the Messenger of Allah (peace be upon him) in his buying and selling with people and the Companions on that basis, without witnessing and writing on that, is the greatest evidence and the greatest sign that the command is not for obligation. Some may be correct when they give an example of a command that is not for obligation, and some may be wrong. And the matter, like all matters of ijtihad (independent legal reasoning), is that a person follows what the evidence establishes, and that is all. As for you imagining that every principle is accepted, meaning one hundred percent, that there is no general rule except what is specified, except very rarely.