Is the ḥadīth: "O Allāh, spare him the torment of the grave and the trial of the grave," which was narrated by Mālik and others from Abū Hurayrah (may Allāh be pleased with him), authentic? And is it permissible to use it as evidence in the issue of the trial of those not held accountable in matters of creed?

This narration was reported by Malik in Al-Muwatta on the authority of Abu Hurairah as mawquf (وقفاً - stopped at a companion), and its chain of transmission is sound. It also came as marfu' (مرفوعاً - attributed to the Prophet), but there is disagreement regarding its chain, and Ibn Taymiyyah deemed it weak. Al-Iraqi pointed to similar marfu' hadiths, including a hadith by Al-Tabarani from Anas and another from Abu Ayyub, whose narrators are those of the Sahih collections, and Al-Albani authenticated it.

This narration and the hadith whose authenticity is debated can serve as evidence that those who are not held accountable (غير المكلفين) are tested in their graves. This is one of the two opinions on the matter and was preferred by Shaykh al-Islam, who stated that the most correct opinion is that they are indeed tested in their graves and instructed. This is what was authentically reported from Abu Hurairah and narrated as marfu' from the Prophet (peace be upon him) that he supplicated for a child for the forgiveness of the torment of the grave.