إِنَّ الَّذِي فَرَضَ عَلَيْكَ الْقُرْآنَ لَرَادُّكَ إِلَىٰ مَعَادٍ (Surely the One who has enjoined the Qur’ an upon you will surely bring you back to a place of return. - 28:85). At the end of Surah these verses were revealed to console the Holy Prophet ﷺ ، and to make him firm in his mission as a messenger. These verses are relevant to the previous verses in that in this Surah, Allah Ta’ ala has narrated in detail the story of Sayyidna Musa (علیہ السلام) with the Pharaoh, his enmity with Bani Isra'il, their fear of him and how he overpowered the people of the Pharaoh. Since the Holy Prophet Muhammad ﷺ faced a similar situation in that he was harassed, and plans were made to kill him, the lives of Muslims were made miserable in Makkah, but following His (Allah) old tradition, Allah graced them with victory over all of them. He finally gifted the Muslims possession of Makkah, from where they were made to vacate.
الَّذِي فَرَضَ عَلَيْكَ الْقُرْآنَ (The One who has enjoined the Qur’ an upon you - 28:85). It means that the Lord of the universe who has made it obligatory on you to recite, teach and act on it, will take you back to Ma` ad, which lexically means 'a place of return'. Sayyidna Ibn ` Abbas ؓ has explained that Ma` ad in this verse refers to Makkah, as reported in Sahih al-Bukhari. So, the meaning of the sentence is that although the Holy Prophet ﷺ would have to leave his hometown, especially the Haram for a short while, he would be brought back in Makkah by Allah Ta’ ala, who had revealed the Qur'an on him, and had made it obligatory to act upon it. The Imam of tafsir, Muqatil, has narrated that during the Hijrah (emigration) from Makkah to Madinah, the Holy Prophet ﷺ came out from the cave of Thaur at night, and by passing the conventional route, treaded the unfamiliar paths, because the enemies were pursuing him. When he reached Juhfah, which was a well-known place on the way to Madinah near Rabigh, and where the conventional route to Madinah separates from that of Makkah, at that time he glanced back toward the route of Makkah and remembered his hometown. On that moment, Jibra'l (علیہ السلام) descended with this verse, in which he was given the good tiding that separation from Makkah was temporary and he would return there soon. That was in fact the advance news of the victory of Makkah. It is in this background that Sayyidna Ibn ` Abbas ؓ has observed in a narration that this verse was revealed in Juhfah, and that it is neither Makki nor Madani. (Qurtubi).
Qur’ an is a means of victory over enemies and of one's success in his objectives
While promising to the Holy Prophet ﷺ that he will be brought back by Allah to his hometown which will be conquered by him, Allah Ta’ ala has made a special reference to Himself as 'the One who has enjoined the Qur’ an on him'. This reference contains a hint to the fact that recitation of Qur’ an and acting on its injunctions would actually be the cause of the Divine help and manifest victory.