“And for their sakes I sanctify myself, that they themselves also may be sanctified in truth.” John "17":19
As the sinless Son of God, Jesus enjoyed a freedom far exceeding any we have on earth. There is much that we may not do or say because we are so full of defects and defilement, but that was never true of Him. And yet, notwithstanding His faultlessness, He deliberately refrained from doing many things which for Him would have been quite legitimate, from speaking many words which He might lawfully have spoken, and from taking many attitudes which He could justifiably have taken. These were some of the ways in which He “sanctified” Himself, refraining from much that was lawful for His disciples’ sake.<br/><br/>What it means is that when holiness was in view, the Lord Jesus thought not merely of His own holiness but of ours. For our sakes, He accepted limitations. The opposite of holiness is not sin but commonness. Commonness "means": I do what is common practice to everyone. Holiness "means": others may do something, but in this instance, at least, I may not. To sanctify ourselves is to accept restraint from God upon our spirits. As with the Lord Jesus, this may often be for the sake of others.