َ يَا أَيُّهَا الَّذِينَ آمَنُوا لَا تَتَوَلَّوْا قَوْمًا غَضِبَ اللَّهُ عَلَيْهِمْ قَدْ يَئِسُوا مِنَ الْآخِرَةِ كَمَا يَئِسَ الْكُفَّارُ مِنْ أَصْحَابِ الْقُبُورِ ﴿۱۳﴾

﴾13﴿ Yaaa ayyuhal lazeena amanoo laa tatawallaw qawman ghadibal laahu 'alaihim qad ya'isoo minal aakhirati kamaa ya'isal kuffaaru min as haabil quboor

﴾13﴿ O believers! Do not befriend those upon whom Allah’s wrath has descended. Indeed, they have despaired of the Hereafter just as the disbelievers have despaired of the resurrection of those in the graves

[13] This verse connects back to the beginning of the surah, which contains the central theme of the surah. At the beginning, disavowal (barā’ah) was commanded generally against the polytheists, and in this verse, disavowal is directed toward the People of the Book who are also polytheists.
(قَدْ يَئِسُوا مِنَ الْآخِرَةِ) — meaning: they have lost hope in the Hereafter’s goodness and reward due to their stubborn opposition to the truth. That is, despite knowing the truth, they deny it out of enmity. Thus, they are fully aware that they have no reward or success in the Hereafter.
(كَمَا يَئِسَ الْكُفَّارُ مِنْ أَصْحَابِ الْقُبُورِ) — "min" here is explanatory (bayāniyyah), meaning: the disbelievers who are now dead have surely lost all hope for reward in the Hereafter.
Or, it could mean: they have lost hope in the living — that the living will do anything beneficial for them.
Or the meaning is: just as all disbelievers have lost hope that the people of the graves (the dead) will ever return to life again.