"And there shall come forth a rod out of the stem of Jesse, and a Branch shall grow out of his roots: And the spirit of the Lord shall rest upon Him, the spirit of wisdom and understanding, the spirit of counsel and might, the spirit of knowledge and of the fear of the Lord" (Isaiah 11:1-2).
This is one of the great prophecies of the Old Testament, clearly foretelling both the human and divine natures of the coming Messiah. Jesse was the father of David whose line of kingly heirs would eventually be cut off by virtue of their sins (e.g., Jeremiah 22:28-30; 36:30). Yet God had also promised David that his seed would, indeed, establish his throne forever (II Samuel 7:16; Jeremiah 33:17).
Therefore, there must somehow arise a "rod" (literally, "shoot") out of the "stem" (literally, "dead stump") of Jesse's family tree, emerging as a live "Branch" from the roots of this tree. This would eventually be fulfilled in Christ's virgin birth, with the legal right to David's throne transmitted through Joseph (see the genealogy in Matthew 1:6-16), but the natural birth from Mary, a descendant of Jesse and David via Nathan, another of David's sons (see Luke 3:23-32) who had not been in the kingly line.
Thus Christ was fully human from conception on, but the conception itself would have to be miraculous. At the same time, He would still retain His divine nature, for the seven spirits of God (note Revelation 1:4) would be fully present in Him. These seven spirits (actually one Holy Spirit, manifest sevenfold as the Spirit of the Lord, of wisdom, of understanding, of counsel, of might, of knowledge, and of the fear of the Lord) would be fully and constantly present in Him. Of no other man in all history could all this be said. Jesus Christ alone has fulfilled Isaiah's ancient prophecy. "In that day there shall be a root of Jesse, . . . and His rest shall be glorious" (Isaiah 11:10). HMM