30 They have also dared to say that the Scripture, When all things shall be subjected unto Him, then shall the Son also Himself be subjected unto Him that subjected all things unto Him —that this Scripture shows that the Son also shall be absorbed into the Father. Shall you then, O most impious of all men, you the creatures of Christ, continue? And shall Christ perish, by whom both you and all things were made? Such a word is blasphemous. But further, how shall all things be made subject unto Him? By perishing, or by abiding? Shall then the other things, when subject to the Son abide, and shall the Son, when subject to the Father, not abide? For He shall be subjected, not because He shall then begin to do the Father's will (for from eternity He does always those things that please Him ), but because, then as before, He obeys the Father, yielding, not a forced obedience, but a self-chosen accordance; for He is not a servant, that He should be subjected by force, but a Son, that He should comply of His free choice and natural love.
Source: Catechetical Lectures (New Advent)