“sanctify” = hagiazo = to separate from the profane and to God; to make holy. They have been born again into a new nature that is not of this world and now they need to act accordingly. Morris states that “They are to be holy men, separated from the world to be of service to the world.” Having men and articles consecrated to God’s service is nothing new (Ex 28:41; 29:1, 36; 40:13) but it is now better because it is based on a more complete revelation.

Exodus 28:41  After you put these clothes on your brother Aaron and his sons, anoint and ordain them. Consecrate them so they may serve me as priests.

Exodus 29:1  “This is what you are to do to consecrate them, so that they may serve me as priests: Take a young bull and two rams without defect.

Exodus 29:36  Sacrifice a bull each day as a sin offering to make atonement. Purify the altar by making atonement for it, and anoint it to consecrate it.

Exodus 40:13  Then dress Aaron in the sacred garments, anoint him and consecrate him so that he may serve me as priest.

Jesus prays that they may be set apart by the truth. This will be accomplished by them doing the truth (3:21). Sanctification is dependant upon the revelation of God. It is only as we come to know Him and what pleases Him that we are able to obey Him and become separate from the world. Sanctification is not received by travailing in prayer nor is it given by the laying on of hands. Sanctification happens when we accept God’s truth in our hearts and make it so much a part of our lives that we live it.

John 3:21  But whoever lives by the truth comes into the light, so that it may be seen plainly that what he has done has been done through God.”

Sanctification or consecration has a two-fold aspect. The first has been noted that it is where we act upon what we know to do. The second is individual settings-apart for a specific work and it is entirely up to God. He chooses who will serve where and gives them whatever gifts and characteristics they need for that ministry. Necessary to both of these aspects of sanctification is the power of God. Without His power there is no gifting or calling and without His power there is no obedience. In (2 Cor 12:10) Paul wrote that “when I am weak, then I am strong” and how true that is, but we often have the misconception that God sends His power to fill in the small cracks of our weaknesses, but the truth is that our weaknesses and inabilities to do His will are not an occasional crack, but instead a huge, gaping cavern. God’s power is an overwhelming necessity in our lives.

2 Corinthians 12:10  That is why, for Christ’s sake, I delight in weaknesses, in insults, in hardships, in persecutions, in difficulties. For when I am weak, then I am strong.

“Your word is truth.” = There is no article with “truth”; if there had been, we might have equated God’s word with truth and made the two interchangeable. His word is more than just true; it is truth; but it is not all of the truth. Truth also contains scientific fact. The earth revolves around the sun; gravity causes apples to drop down out of trees instead of upwards or sideways; to every action there is an opposite and equal reaction. These are all part of truth. But as Dr. Francis Collins, the head of the Human Genome Project, said, “God is not afraid of scientific truth. How could he be? He invented it.” (qt’d in Guideposts, Dec. 2006, p. 44) Essentially, truth is God’s nature finding its expression in creation (Rom 1:20), in revelation (in this verse Jesus says “your word is truth”), and ultimately in Jesus Christ (John 14:6). We should never be afraid of discovering the truth because all truth comes from God. 40% of all scientists believe in a God who answers prayer. The other 60% don’t because they are operating under the false premise that there is no God and therefore they do not look at the facts objectively. God is the Author of truth and when we honestly look at the truth we will see Him.

Romans 1:20  For since the creation of the world God’s invisible qualities—his eternal power and divine nature—have been clearly seen, being understood from what has been made, so that men are without excuse.

John 14:6  Jesus answered, “I am the way and the truth and the life. No-one comes to the Father except through me.

Jesus earlier said that His own word was truth and that it made men free (8:31-32). The Father’s word is similar. It is truth and must be immediately accepted and acted upon. God’s revealed truth is not something to be learned and then filed away in our memories; it is something to be apprehended and then acted upon. This is the manner in which men are sanctified.

John 8:31-32  To the Jews who had believed him, Jesus said, “If you hold to my teaching, you are really my disciples.  Then you will know the truth, and the truth will set you free.”