Here Allah commands His servants to hasten to obedience to Him and to hasten to do good deeds.

فَأَقِمْ وَجْهَكَ لِلدِّينَ الْقِيِّمِ مِن قَبْلِ أَن يَأْتِىَ يَوْمٌ لاَّ مَرَدَّ لَهُ مِنَ اللَّهِ

(So, set you your face to the straight and right religion, before there comes from Allah a Day which none can avert.) The Day of Resurrection, for when Allah wants it to happen, no one will be able to avert it.

يَوْمَئِذٍ يَصَّدَّعُونَ

(On that Day men shall be divided.) means, they will be separated, with one group in Paradise and another in Hell. Allah says:

مَن كَفَرَ فَعَلَيْهِ كُفْرُهُ وَمَنْ عَمِلَ صَـلِحاً فَلاًّنفُسِهِمْ يَمْهَدُونَ لِيَجْزِىَ الَّذِينَ ءَامَنُواْ وَعَمِلُواْ الصَّـلِحَـتِ مِن فَضْلِهِ

(Whosoever disbelieves will suffer from his disbelief, and whosoever does righteous good deeds, then such will prepare a good place for themselves. That He may reward those who believe. and do righteous good deeds, out of His bounty.) meaning that He may reward them from His bounty, in return for one good deed, he will get the reward for ten, up to seven hundred like it, as much as Allah wills.

إِنَّهُ لاَ يُحِبُّ الْكَـفِرِينَ

(Verily, He likes not the disbelievers.) yet He is still just with them and does not oppress them.