وَرَبُّكَ أَعْلَمُ بِمَن فِي السَّمَاوَاتِ وَالَارْضِ
And your Lord knows best all who are in the heavens and the earth.
meaning, their status or level of obedience or disobedience.
The Preference of some Prophets above Others
Allah says;
وَلَقَدْ فَضَّلْنَا بَعْضَ النَّبِيِّينَ عَلَى بَعْضٍ
And indeed, We have preferred some of the Prophets above others.
As Allah says;
تِلْكَ الرُّسُلُ فَضَّلْنَا بَعْضَهُمْ عَلَى بَعْضٍ مِّنْهُمْ مَّن كَلَّمَ اللَّهُ وَرَفَعَ بَعْضَهُمْ دَرَجَـتٍ
Those Messengers! We preferred some of them to others; to some of them Allah spoke (directly); others He raised to degrees (of honor). (2;253)
This does not contradict the report in the Two Sahihs which says that the Messenger of Allah said;
لَاا تُفَضِّلُوا بَيْنَ الاْاَنْبِيَاء
Don't give superiority to any Prophet among (Allah's) Prophets.
What is meant in this Hadith is giving a superiority based on whims and fanaticism or sectarian feelings, not on the basis of evidence. If there is solid evidence, we have to follow it. There is no dispute that the Messengers are better than the rest of the Prophets, and that the mighty Messengers of Great Resolve are the best of all. They are the five mentioned in two Ayat of the Qur'an, in Surah Al-Ahzab;
وَإِذْ أَخَذْنَا مِنَ النَّبِيِّيْنَ مِيثَاقَهُمْ وَمِنْكَ وَمِن نُّوحٍ وَإِبْرَهِيمَ وَمُوسَى وَعِيسَى ابْنِ مَرْيَمَ
And (remember) when We took from the Prophets their covenant, and from you and from Nuh, Ibrahim, Musa and `Isa son of Maryam. (33;7)
and in Surah Ash-Shura;
شَرَعَ لَكُم مِّنَ الِدِينِ مَا وَصَّى بِهِ نُوحاً وَالَّذِى أَوْحَيْنَأ إِلَيْكَ وَمَا وَصَّيْنَا بِهِ إِبْرَاهِيمَ وَمُوسَى وَعِيسَى أَنْ أَقِيمُواْ الدِّينَ وَلَا تَتَفَرَّقُواْ فِيهِ
He has ordained for you the same religion which He ordained for Nuh, and that which We have revealed to you, and that which We ordained for Ibrahim, Musa and `Isa saying you should establish religion and make no divisions in it. (42;13)
There is no dispute that Muhammad is the best of them, then Ibrahim, then Musa, then `Isa (peace be upon them all), according to the best-known view.
We have discussed the evidence for this in detail elsewhere, and Allah is the source of help.
Allah's saying,
وَاتَيْنَا دَاوُودَ زَبُورًا
and to Dawud We gave the Zabur.
is an indication of his virtue and honor.
Al-Bukhari recorded from Abu Hurayrah that the Prophet said;
خُفِّفَ عَلَى دَاوُدَ الْقُرْانُ فَكَانَ يَأْمُرُ بِدَوَابِّهِ فَتُسْرَجُ فَكَانَ يَقْرَوُهُ قَبْلَ أَنْ يَفْرُغ
The Qur'an (i.e. revealed Scripture of Zabur) was made easy for Dawud, so he would call for his mounts to be saddled, and he would finish reciting it (i.e., the Zabur) before the job was done