The Family of Imran
وَمَا جَعَلَهُ ٱللَّهُ إِلَّا بُشْرَىٰ لَكُمْ وَلِتَطْمَئِنَّ قُلُوبُكُم بِهِۦ ۗ وَمَا ٱلنَّصْرُ إِلَّا مِنْ عِندِ ٱللَّهِ ٱلْعَزِيزِ ٱلْحَكِيمِ
And Allah made it not except as [a sign of] good tidings for you and to reassure your hearts thereby. And victory is not except from Allah, the Exalted in Might, the Wise -
Nearby ayahs help place verse 3:126 in sequence and meaning.
إِذْ تَقُولُ لِلْمُؤْمِنِينَ أَلَن يَكْفِيَكُمْ أَن يُمِدَّكُمْ رَبُّكُم بِثَلَـٰثَةِ ءَالَـٰفٍ مِّنَ ٱلْمَلَـٰٓئِكَةِ مُنزَلِينَ
[Remember] when you said to the believers, "Is it not sufficient for you that your Lord should reinforce you with three thousand angels sent down?
بَلَىٰٓ ۚ إِن تَصْبِرُوا۟ وَتَتَّقُوا۟ وَيَأْتُوكُم مِّن فَوْرِهِمْ هَـٰذَا يُمْدِدْكُمْ رَبُّكُم بِخَمْسَةِ ءَالَـٰفٍ مِّنَ ٱلْمَلَـٰٓئِكَةِ مُسَوِّمِينَ
Yes, if you remain patient and conscious of Allah and the enemy come upon you [attacking] in rage, your Lord will reinforce you with five thousand angels having marks [of distinction]
لِيَقْطَعَ طَرَفًا مِّنَ ٱلَّذِينَ كَفَرُوٓا۟ أَوْ يَكْبِتَهُمْ فَيَنقَلِبُوا۟ خَآئِبِينَ
That He might cut down a section of the disbelievers or suppress them so that they turn back disappointed.
لَيْسَ لَكَ مِنَ ٱلْأَمْرِ شَىْءٌ أَوْ يَتُوبَ عَلَيْهِمْ أَوْ يُعَذِّبَهُمْ فَإِنَّهُمْ ظَـٰلِمُونَ
Not for you, [O Muhammad, but for Allah], is the decision whether He should [cut them down] or forgive them or punish them, for indeed, they are wrongdoers.