We went out with God’s messenger to Sa'd b. Mu'adh when he died. God’s messenger prayed over him, and when he was placed in his grave and the ground was levelled over him, God’s messenger extolled God and we did so also at great length. He then said, “God is most great," and we did the same. Someone asked him why he had extolled God and then said, “God is most great," to which he replied, “This upright servant’s grave had closed in on him, but finally God removed the pressure from him."
Abu Sa'id reported God’s messenger as saying, “Ninety-nine dragons will be given power over an infidel in his grave, and will bite and sting him till the last hour comes. If one of those dragons were to breathe over the earth, it would bring forth no green thing."
Darimi transmitted it, and Tirmidhi transmitted something similar, but he said seventy instead of ninety-nine.
Ibn ‘Umar reported God’s messenger as saying, “This is the one1 on account of whom the throne moved, for whom the gates of heaven were opened, and whose funeral seventy thousand angels attended. He was compressed, but afterwards the pressure was removed from him."
He also said that when the Prophet finished the burial of the dead he stood over it and said, “Ask forgiveness for your brother, then ask that he may be strengthened, for he is now being questioned."