Surah Al An'am Tafseer

إِنَّمَا يَسْتَجِيبُ الَّذِينَ يَسْمَعُونَ

It is only those who listen, that will respond,

means, only those who hear the speech, comprehend and understand it, will accept your call, O Muhammad!

In another Ayah, Allah said;

لِّيُنذِرَ مَن كَانَ حَيّاً وَيَحِقَّ الْقَوْلُ عَلَى الْكَـفِرِينَ

That it may give warning to him who is living, and that the Word may be justified against the disbelievers. (36:70)

Allah's statement,

وَالْمَوْتَى يَبْعَثُهُمُ اللّهُ ثُمَّ إِلَيْهِ يُرْجَعُونَ

but as for the dead, Allah will raise them up, then to Him they will be returned.

refers to the disbelievers because their hearts are dead. Therefore, Allah resembled them to dead corpses as a way of mocking and belittling them, saying,

(but as for the dead (disbelievers), Allah will raise them up, then to Him they will be returned (for their recompense)