And they took their bones, and buried them under a tree at Jabesh, and {f} fasted seven days.

(f) According to the custom of mourners.

Wesley's Notes

31:13 Fasted - To testify their sorrow for the loss of Saul, and of the people of God; and to intreat God's favour to prevent the utter extinction of his people. But you must not understand this word of fasting strictly, as if they eat nothing for seven whole days; but in a more large sense, as it is used both in sacred and profane writers; that they did eat but little, and that but mean food, and drank only water for that time. This book began with the birth of Samuel, and ends with the death of Saul: The comparing these together will teach us to prefer the honour that comes from God, before all the honours of the world.

Matthew Henry's Concise Commentary

31:8-13 The Scripture makes no mention what became of the souls of Saul and his sons, after they were dead; but of their bodies only: secret things belong not to us. It is of little consequence by what means we die, or what is done with our dead bodies. If our souls are saved, our bodies will be raised incorruptible and glorious; but not to fear His wrath, who is able to destroy both body and soul in hell, is the extreme of folly and wickedness. How useless is the respect of fellow-creatures to those who are suffering the wrath of God! While pompous funerals, grand monuments, and he praises of men, honour the memory of the deceased, the soul may be suffering in the regions of darkness and despair! Let us seek that honour which cometh from God only.