When Jesus was on earth he was said to be “lower than the...

When Jesus was on earth he was said to be “lower than the angels”. Man is lower than angels. Certainly one who is in the flesh is lower than one who is in the spirit. God often contrasts flesh and spirit. (Ps. 8:4, 5; Heb. 2:9; Isa. 31:3) Could you believe that Jesus Christ, the majestic King of the new world, made higher than all other creation, would remain in a body of flesh? He would be inferior to a spirit and far too limited to accomplish the marvelous things required of such King, among them the destroying of the mighty spirit person Satan the Devil.
He manifested himself on one occasion in a body that had wounds into which Thomas was able to place his hands to prove that Jesus was the same person, resurrected, whom Thomas had known as the Master. If Jesus sacrificed his human body for the life of the world and then took it back, retaining it for himself, he could not offer such merit before God in behalf of others. The ransom would be taken back, leaving mankind still in their sins.
So these bodies that Jesus appeared in after his resurrection were materialized bodies. Similar instances occurred in ancient times, such as when the three men visited and ate with Abraham, and those appearing to Lot, in each case being angels who materialized in the form of men. Jesus’ materialized bodies were signs, evidences to eyewitnesses proving he had been resurrected according to the promise of Jehovah God.—Gen. 18:1-22; 19:1-16; John 20:29-31.
The proofs that these were bodies materialized for the occasion are many. Mary, when she first saw Jesus after his resurrection, did not recognize him, thinking that he must be the gardener. On the road to Emmaus, he was recognized by his manners and actions, not by his facial features. (John 20:14-16; Luke 24:13-32; Mark 16:12) When he materialized a body with wound marks to convince the doubtful Thomas, Jesus appeared in a room with locked doors. (John 20:26-28) This shows that he could materialize and dematerialize a body instantaneously. Scientists claim the ability to make material substance out of pure energy. How easy for the power of the resurrected Jesus, then, to materialize a body!
  The apostle Peter, who had spoken with the resurrected Jesus, could then later write under inspiration:
(1 Peter 3:18) For Christ died once for all time for sins, a righteous person for unrighteous ones, in order to lead you to God. He was put to death in the flesh but made alive in the spirit.