Word by Word Analysis

فَأَقِمْ وَجْهَكَ لِلدِّينِ ٱلْقَيِّمِ مِن قَبْلِ أَن يَأْتِىَ يَوْمٌ لَّا مَرَدَّ لَهُۥ مِنَ ٱللَّهِ ۖ يَوْمَئِذٍ يَصَّدَّعُونَ 43

So direct your face [i.e., self] toward the correct religion before a Day comes from Allāh of which there is no repelling. That Day, they will be divided.