In that day I will perform against Eli all things which I have spoken concerning his house: when I begin, I will also make an end.
In that day I will perform against Eli all things which I have spoken concerning his house - i:e., at the time appointed; and in the course of Providence, which was between 20 and 30 years of this prophetic denunciation, the judgments threatened by the man of God (1 Samuel 2:27) began to be inflicted.
When I begin, I will also make an end. Judgment being God's strange work, He long delays it, and in the exercise of long-suffering patience affords ample time for repentance. But when the period of grace expires, the judicial infliction commences, and will be carried on until the vial of divine wrath is emptied.