They deem it to be a favour to you that they have submitted without the need for any fighting unlike those others who submitted only after being fought. Say ‘Do not deem your submission to be a favour to me islāmakum ‘your submission’ has dependent accusative status because of the omission of the genitive preposition bi-which is also read as implicit before the an in both instances. Rather it is God Who has done you a favour in that He has guided you to faith if you are being sincere when you say ‘We believe’.