Abbas - Tanwîr al-Miqbâs min Tafsîr Ibn ‘Abbâs
Allah then reminded them of the evanescence of this world and of the continuity of the Hereafter, and encouraged them to seek the latter, saying: (Let not the vicissitude (of the success) of those who disbelieve in the land) the coming and going of the Jews for trade, (deceive thee) O Muhammad! Although Muhammad is here the addressee, this is directed at his Companions.
When the Muslims began to say, ‘Look at the enemies of God, how comfortable they are, while we are struggling!’, the following was revealed: Let it not delude you, that the disbelievers go to and fro in the land, engaging in commerce and acquiring profit:
Do not be deluded by the going to and fro of the disbelievers, those who have been veiled from the affirmation of the Oneness, which is the religion of the truth with respect to all stations and states;
Warning Against Being Deceived by This Life; the Rewards of the Righteous Believers
Allah said, do not look at the disbelievers, who are enjoying various delights and joys. Soon, they will loose all this and be tied to their evil works, for verily, we are only giving them time, which deceives them, when all they have is,
(Verily, those who invent a lie against Allah, will never be successful. (A brief) enjoyment in this world! and then unto Us will be their return, then We shall make them taste the severest torment because they used to disbelieve.) 10:69,70,
(Is he whom We have promised an excellent promise (Paradise) which he will find true -- like him whom We have made to enjoy the luxuries of the life of (this) world, then on the Day of Resurrection, he will be among those brought up (to be punished in the Hell-fire)) 28:61.
After Allah mentioned the condition of the disbelievers in this life and their destination to the Fire, He said,
(And let not the disbelievers think that Our postponing of their punishment is good for them. We postpone the punishment only so that they may increase in sinfulness. And for them is a disgraceful torment.) 3:178.''
Let it not delude you that the disbelievers go to and fro in the land a little enjoyment; then their abode is hell-an evil cradling! “Do not let any doubt seize you thinking that they have any value or worth with Us. Rather the days are few and breaths limited. Afterward there will be grief upon grief ḥasarāt mutarādifa and sorrow upon sorrow aḥzān mutaḌāʿifa.”
(Let not the vicissitude (of the success) of those who disbelieve, in the land, deceive thee…) [3:196]. This was revealed about the idolaters of Mecca. This is because they were living in comfort and ease, trading and enjoying themselves which led one believer to comment: “The enemies of Allah are enjoying that which we see of goodly life while we are dying of hunger and toil”, and as a result this verse was revealed.