عَلَى أَن نُّبَدِّلَ خَيْرًا مِّنْهُمْ
But no!
I swear by the Lord of the easts and the wests that surely We are Able to replace them by (others) better than them..
meaning, `on the Day of Judgement We will bring them back (to life) in bodies that are better than these bodies that they have now.'
For verily, Allah's power is suitable (able) to do that.
وَمَا نَحْنُ بِمَسْبُوقِينَ
and We are not to be outrun.
meaning, `We are not unable.'
This is as Allah says,
أَيَحْسَبُ الاِنسَـنُ أَلَّن نَّجْمَعَ عِظَامَهُ بَلَى قَـدِرِينَ عَلَى أَن نُّسَوِّىَ بَنَانَهُ
Does man think that We shall not assemble his bones?
Yes, We are able to put together in perfect order the tips of his fingers. (75;3,4)
Allah also says,
نَحْنُ قَدَّرْنَا بَيْنَكُمُ الْمَوْتَ وَمَا نَحْنُ بِمَسْبُوقِينَ
عَلَى أَن نُّبَدِّلَ أَمْثَـلَكُمْ وَنُنشِيَكُمْ فِى مَا لَا تَعْلَمُونَ
We have decreed death to you all, and We are not outstripped. To transfigure you and create you in (forms) that you know not. (56;60,61)
Ibn Jarir preferred the meaning to be;
`a nation who will obey Us and not disobey Us.'
He (Ibn Jarir) interpreted it in the same way as Allah's statements,
عَلَى أَن نُّبَدِّلَ خَيْرًا مِّنْهُمْ
(To replace them by (others) better than them..) and;
الْفُقَرَاءُ وَإِن تَتَوَلَّوْاْ يَسْتَبْدِلْ قَوْماً غَيْرَكُمْ ثُمَّ لَا يَكُونُواْ
And if you turn away, He will exchange you for some other people and they will not be like you. (47;38)
However, the first interpretation is more obvious since the other Ayat support that, and Allah the Most High knows best.
Then Allah says