We have stated already that the Shariat has stipulated the undertaking of jihad to remove the obstacles placed in propagating Islam. Jihad is very important. Everybody knows that. Nevertheless the importance of ‘ilme Deen is such that all have been forbidden to go out in jihad all at once, but the command has been given that a group should remain behind in the presence of Rasulullah (sallallahu alaiyhi wassallam) in order to learn ‘ilme Deen.
The importance of the jihad of acquiring ‘ilm in relation to physical jihad-eamali is such that the latter (jihad-e-amali) is dependant on the former: if one does not have correct ‘ilm, according to the Haq of the Shariat and the limits of the Shariat, what will be the state of one’s jihad? It will definitely not be according to the wishes of Allah Ta’ala.
That is why Allah Ta’ala says: Do not go out all together, if it is not a situation of nafir-e-am (general hostilities). No, do not do such a thing. Rather a jama’t (group) from amongst you should stay in your (Rasulullah sallaahu alaiyhi wassallam’s) presence to acquire ‘ilm, while some should go out in jihad.
The elevated status and importance of acquiring ‘ilm is being emphasised. Staying put in one place for the jihad of acquiring ‘ilm is also a burden on the nafs – one is restricted, one’s freedom is curtailed, one has to be punctual. This is a jihad against the nafs.
Allah Ta’ala then says: Those who return from jihad should now be taught by those who had remained behind in the royal court of Rasulullah (sallallahu alaiyhi wassallam) what they had learnt. The word used is “fiqah” – the correct understanding: to be able to comprehend and explain. “Liyatafaqqahu fid din” – the plural used denotes that the students of Rasulullah (sallallahu alaiyhi wassallam) are being addressed.
One can see how a chain has formed. Starting from Rasulullah (sallallahu alaiyhi wassallam), ‘ilm has been passed on to his students; his students have, in turn, become ustads (teachers.), and those returning are now the students, for ‘ilm to be passed on to them.
Source: For Friends