The Victory
وَعَدَكُمُ ٱللَّهُ مَغَانِمَ كَثِيرَةً تَأْخُذُونَهَا فَعَجَّلَ لَكُمْ هَـٰذِهِۦ وَكَفَّ أَيْدِىَ ٱلنَّاسِ عَنكُمْ وَلِتَكُونَ ءَايَةً لِّلْمُؤْمِنِينَ وَيَهْدِيَكُمْ صِرَٰطًا مُّسْتَقِيمًا
Allah has promised you much booty that you will take [in the future] and has hastened for you this [victory] and withheld the hands of people from you - that it may be a sign for the believers and [that] He may guide you to a straight path.
Nearby ayahs help place verse 48:20 in sequence and meaning.
۞ لَّقَدْ رَضِىَ ٱللَّهُ عَنِ ٱلْمُؤْمِنِينَ إِذْ يُبَايِعُونَكَ تَحْتَ ٱلشَّجَرَةِ فَعَلِمَ مَا فِى قُلُوبِهِمْ فَأَنزَلَ ٱلسَّكِينَةَ عَلَيْهِمْ وَأَثَـٰبَهُمْ فَتْحًا قَرِيبًا
Certainly was Allah pleased with the believers when they pledged allegiance to you, [O Muhammad], under the tree, and He knew what was in their hearts, so He sent down tranquillity upon them and rewarded them with an imminent conquest
وَمَغَانِمَ كَثِيرَةً يَأْخُذُونَهَا ۗ وَكَانَ ٱللَّهُ عَزِيزًا حَكِيمًا
And much war booty which they will take. And ever is Allah Exalted in Might and Wise.
وَأُخْرَىٰ لَمْ تَقْدِرُوا۟ عَلَيْهَا قَدْ أَحَاطَ ٱللَّهُ بِهَا ۚ وَكَانَ ٱللَّهُ عَلَىٰ كُلِّ شَىْءٍ قَدِيرًا
And [He promises] other [victories] that you were [so far] unable to [realize] which Allah has already encompassed. And ever is Allah, over all things, competent.
وَلَوْ قَـٰتَلَكُمُ ٱلَّذِينَ كَفَرُوا۟ لَوَلَّوُا۟ ٱلْأَدْبَـٰرَ ثُمَّ لَا يَجِدُونَ وَلِيًّا وَلَا نَصِيرًا
And if those [Makkans] who disbelieve had fought you, they would have turned their backs [in flight]. Then they would not find a protector or a helper.