Reason of revelation:
Thawban (May Allah be pleased with him), was a lover of the Prophet who could not put up with being separated from him. Once, he came to the presence of the Messenger of Allah in a terrible state. His face was pale, his body was weak and there was an expression of sorrow in his face. When the Prophet (saws) saw him like that, he asked him, “O Thawban! What has happened? Are you ill? Thawban replied as follows: “O Messenger of Allah! I am not ill nor have I any pain but when I do not see you, my love toward you increases; I feel grievous until I rejoin you. Then, I remember the hereafter and fear that I will not be able to see you there. For, you will be in a higher station with the prophets in Paradise and I will be in a lower position. I am worried that I will not be able to see you there.” Consequently, this verse was revealed.
(… وَمَن يُطِعِ اللَّهَ وَالرَّسُولَ ) (And whoever obeys Allah and the Messenger – …): Allah (swt) makes it clear that to obey the Prophet (saws) is to obey Allah (swt), so mentioned one word of “obeys” for Allah (swt) and the Messenger (saws), because it is not possible to separate what the Messenger (saws) has come with from the verses of the Holy Qur’an.
(… فَأُولَٰئِكَ مَعَ الَّذِينَ أَنْعَمَ اللَّهُ عَلَيْهِم مِّنَ النَّبِيِّينَ وَالصِّدِّيقِينَ وَالشُّهَدَاءِ وَالصَّالِحِينَ…) (…– those will be with the ones upon whom Allah has bestowed favor of the prophets, the steadfast affirmers of truth, the martyrs and the righteous…): This favor from Allah (swt) equals all the bestowments. Those will be with the Prophets and Messengers in the first grade and with the righteous in the second grade. Righteousness is the state of having absolute faith, as Abo Bakr Al-Seddiq (May Allah be pleased with him), when he was told that the Prophet (saws) had the night journey and ascension to the seventh heaven and then came back in the same night, he said: “I do believe him regarding what is farther than that. I believe the news of heaven he brings, so if he told that, then he said the truth”. Because of this Abu Bakr was named al-Siddiq (The righteous).
The martyrs are in the highest level of Paradise, they are alive with their Lord:
وَلَا تَحْسَبَنَّ الَّذِينَ قُتِلُوا فِي سَبِيلِ اللَّهِ أَمْوَاتًا ۚ بَلْ أَحْيَاءٌ عِندَ رَبِّهِمْ يُرْزَقُونَ
(And never think of those who have been killed in the cause of Allah as dead. Rather, they are alive with their Lord, receiving provision,) (Ali-Imran: 169)
They live with the grace and bounty of Allah (swt), and this is also good tidings for their families and the righteous who follow the path of the Prophets, the truthful ones, and the martyrs.
( وَحَسُنَ أُولَٰئِكَ رَفِيقًا … ) (…And excellent are those as companions): The companion is the friendly person who guides you and keeps with you throughout the path, and the best companionship of all is to be with the Prophets, the truthful ones, the martyrs and the righteous.