وَمَا كَانَ لَهُۥ عَلَيْهِم مِّن سُلْطَـٰنٍ إِلَّا لِنَعْلَمَ مَن يُؤْمِنُ بِٱلْـَٔاخِرَةِ مِمَّنْ هُوَ مِنْهَا فِى شَكٍّ ۗ وَرَبُّكَ عَلَىٰ كُلِّ شَىْءٍ حَفِيظٌ 
  Wam a  k a na lahu AAalayhim min sul ta nin ill a  linaAAlama man yuminu bi a l a khirati mimman huwa minh a  fee shakkin warabbuka AAal a  kulli shayin  h afee  th   un      And yet, he had no power at all over them:30 [for if We    allow him to tempt man,] it is only to the end that We might make    a clear distinction between those who [truly] believe in the life    to come and those who are in doubt thereof:31 for thy    Sustainer watches over all things.
   - Mohammad Asad
 
        
    
        
    
    
even though he had no authority over them. It all happened    because We wanted to see who among them believed in the hereafter    and who is in doubt concerning it. Your Rabb is watching over all    things.
   - Muhammad Farooq-i-Azam Malik
   He does not have any authority over them, but 'Our Will is' only to distinguish those who believe in the Hereafter from those who are in doubt about it. And your Lord is a 'vigilant' Keeper over all things.'
   - Mustafa Khattab
     
And he had no warrant whatsoever against them, save that We would    know him who believeth in the Hereafter from him who is in doubt    thereof; and thy Lord (O Muhammad) taketh note of all things.
   - Marmaduke Pickthall
   But he had no authority over them except that We might test the    man who believes in the Hereafter from him who is in doubt    concerning it: and thy Lord doth watch over all things.    3821
   - Abdullah Yusuf Ali