Question: “When Jesus came down, and was born as a human being, unto Mary and Joseph,
and gave up His omnipotence, was this forever, or, when He was raised from
the tomb, and returned to the Father, did He regain His omnipotence?”

Answer: Yes, Jesus did regain His omnipotence or “almighty” power after He was raised from the tomb. He was reinstated with the Father and the Holy Spirit (Revelation 4:8). The word “omnipotent” is “pantokrator” in the Greek and is translated “Almighty” in most Bible translations (see Revelation 11:17; 15:3; 16:7, 14; 19:15; 21:22). It is specifically applied to Christ in the book of Revelation as the following verse indicates. 

“Behold, he cometh with clouds; and every eye shall see Him, and they also which pierced Him: and all kindreds of the earth shall wail because of Him. Even so, Amen. I am Alpha and Omega, the beginning and the ending, saith the Lord, which is, and which was, and which is to come, the Almighty” (Revelation 1:7-8).

This previous verse says that the Lord is “almighty” or omnipotent (pantokrator) and that He is the Alpha and Omega. The following verses show that Jesus is Alpha and Omega and therefore the Lord being spoken of in the previous verses:

“I was in the Spirit on the Lord’s day, and heard behind me a great voice, as of a trumpet, saying, I am Alpha and Omega, the first and the last: and, What thou seest, write in a book, and send it unto the seven churches which are in Asia; unto Ephesus, and unto Smyrna, and unto Pergamos, and unto Thyatira, and unto Sardis, and unto Philadelphia, and unto Laodicea. And I turned to see the voice that spake with me. And being turned, I saw seven golden candlesticks; And in the midst of the seven candlesticks one like unto the Son of man, clothed with a garment down to the foot, and girt about the paps with a golden girdle” (Revelation 1:10-13).

“And, behold, I come quickly; and my reward is with me, to give every man according as his work shall be. I am Alpha and Omega, the beginning and the end, the first and the last. Blessed are they that do his commandments, that they may have right to the tree of life, and may enter in through the gates into the city. For without are dogs, and sorcerers, and whoremongers, and murderers, and idolaters, and whosoever loveth and maketh a lie. I Jesus have sent mine angel to testify unto you these things in the churches. I am the root and the offspring of David, and the bright and morning star” (Revelation 22:12-16).