2 Kings 22:20 - Joseph Benson’s Commentary on the Old and New Testaments

Behold, therefore, I will gather thee to thy fathers It is justly observed here by Henry, that the saints in those days had doubtless a comfortable prospect of happiness on the other side of death, otherwise the being gathered to their fathers would not have been so often made the matter of a promise as we find it was. Josiah could not prevail to prevent the judgment itself, but God promised him he should not live to see it; which, especially considering that he died in the midst of his days, before he was forty years of age, would have been but a small reward for his eminent piety, if there had not been another world, in which he should be abundantly recompensed, Hebrews 11:16. When the righteous is taken away from the evil to come, he enters into peace, Isaiah 58:1-2. This is promised to Josiah here, Thou shalt go to thy grave in peace Which refers not to the manner of his death, for he was killed in battle, but to the time of it; it was a little time before the captivity in Babylon, that great trouble, in comparison with which other troubles were as nothing: so that he might be truly said to die in peace, that did not live to share in that. He died in the love and favour of God, which secures such a peace as no circumstances of dying, no, not dying in the field of war, could alter the nature of, or break in upon. They may well be said to die in peace, who, after their dissolution here, are numbered among the children of God, and have their lot among the saints.