Imam Ahmad recorded that `Abdullah bin Salam said, "We asked, `Who among us should go to the Messenger ﷺ and ask him about the dearest actions to Allah' None among us volunteered. The Messenger ﷺ sent a man to us and that man gathered us and recited this Surah, Surat As-Saff, in its entirety."'
بِسْمِ اللَّهِ الرَّحْمَـنِ الرَّحِيمِ
In the Name of Allah, the Most Gracious, the Most Merciful.
Chastising Those Who say what They do not do
We mentioned in many a places before the meaning of Allah's statement,
(Whatsoever is in the heavens and whatsoever is on the earth glorifies Allah. And He is the Almighty, the All-Wise.) Therefore, we do not need to repeat its meaning here. Allah's statement,
(0 those who believe, why do you say what you do not do? It is severely hateful in Allah's sight that you say what you do not do...61:2-3)
Apparently, the phrase 'what you do not do' implies that one should not claim to do something he does not intend to do. From this it may be deduced that it is prohibited to make a commitment to do a work while a person does not have the genuine intention to really do it, because this would be ostentation and a false commitment. Obviously, the blessed Companions, in the story of the background of revelation, were not making such promises without having intention to fulfill them. Instead, their intention was genuine. From this we learn that the verse includes a situation where a person commits to do something with true intention to do it, but relies solely on his own strength, it is not in keeping with his station of ` abdiyyah or 'servitude'. First of all, there is no need to make such a claim. If the occasion does arise to do something, he may go ahead and do it. If, for some reason or the other, a person has to make a promise or claim, he may affirm it by saying 'If Allah wills'. In this way, it would not be a boastful claim.