O you who have believed, do not ask about things which, if they are shown to you, will distress you. But if you ask about them while the Qur’an is being revealed, they will be shown to you. Allah has pardoned that which is past; and Allah is Forgiving and Forbearing.
The meaning of this statement is best explained by the author of Maariful Hadith in these words:
“It is natural for man to be inquisitive but if he is allowed to indulge freely in the habit he tends to make minute distinctions in argument and a corresponding weakening of the capacity for action takes place. Much time is also wasted in it” (Vol. 1 pg. 92)
The Background of the Revelation
When the verse concerning the obligation of Hajj was revealed, obligation of Hajj was revealed, Sayyidna Al-Aqra’ ibn Hiibis asked: ‘Have we been obligated with Hajj every year?’ The Holy Prophet (peace be upon him) did not answer that question. He asked again. The Holy Prophet (pbuh) still remained silent. When he asked a third time, the Holy Prophet (pbuh) reprimanded him by saying: If, in answer to your question, I had said, ‘Yes, the Hajj is obligatory every year’ – so it would have become, and you would have been unable to do it. After that, he added: Things about which I give you no command, leave them as they are. Do not ask questions by digging and prying into them. Communities before you have been damned eternally through this very proliferation of questioning because they, questions after questions about what Allah and His Messenger did not make obligatory on them, and in consequence of their unnecessary enquiry, these optional things were made obligatory – and then, they got involved in the unfortunate practice of disobeying these. Your established routine should be: Do what I order you to do, with the best of your ability, and leave what I order you not to do (that is, do not dig and pry into things about which no injunctions are given). [Maariful Quran Vol 3 pg. 266]
As for the large body of work left by Muslim jurists in which they have answered assumed religious problems and questions, it was not something unnecessary. Later events proved that they were needed by future generations. Therefore, they do not fall under the purview of wasteful or meaningless questions. [Maariful Quran Vo. 3 pg. 267]