All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
It is better to read the chapters according to their order in the Mus-haf whether in or out of prayer. Contradicting this is disliked and is called Tankees in recitation. It is not forbidden, due to a narration in which the Prophet, sallallaahu ‘alayhi wa sallam, once started his night prayers with Al-Baqarah Chapter, then An-Nisaa’ then Aal-‘Imraan, diverging from the order of the Mus-haf. [Narrated by Muslim on the authority of Huthayfah, may Allaah Be Pleased with him] On the other hand, preserving the order of verses is obligatory and reversing them is forbidden as this order is dictated by revelation to the Prophet, sallallaahu ‘alayhi wa sallam. It was narrated in Sunan An-Nasaa’i Al-Kubra and others on the authority of ‘Uthmaan, may Allaah Be Pleased with him, that upon revelation, the Prophet, sallallaahu ‘alayhi wa sallam, used to call upon some of those who write and say “insert these in the chapter that contains such and such”. The Maaliki school adopts the view that changing the order of verses nullifies the prayer. As-Saawi said: “It is forbidden to reverse the order of consecutive verses in one Rak‘ah. This renders the prayer invalid because it turns it to a speech irrelevant to the Quran.”
Allaah Knows best.