Genesis 49:10
9 You are a lion’s cub, Judah, from the prey, my son, you have gone up. He crouches and lies down like a lion; like a lioness—who will rouse him? 10 The scepter will not depart from Judah, nor the ruler’s staff from between his feet, until he comes to whom it belongs; the nations will obey him. 11 Binding his foal to the vine, and his colt to the choicest vine, he will wash his garments in wine, his robes in the blood of grapes.
Onkelos Genesis 49:10
9 The dominion shall be (thine) in the beginning, and in the end the kingdom shall be increased from the house of Jehuda, because from the judgment of death, my son, hast thou withdrawn. He shall repose, and abide in strength as a lion, and as a lioness, there shall be no king that may cut him off. 10 He who exerciseth dominion shall not pass away from the house of Jehuda, nor the saphra from his children's children for ever, until the Meshiha come, whose is the kingdom, and unto whom shall be the obedience of the nations (or, whom the peoples shall obey). 11 Israel shall pass round about in his cities; the people shall build his temple, they will be righteous round about him, and be doers of the law through his doctrine. Of goodly purple will be his raiment, and his vesture of crimson wool with colours.
Notes and References
"... But, of course, the scepter did depart from Judah. Centuries later, the Jewish homeland was conquered by the Babylonians in 587 B.C.E. The king, scion of the Davidic dynasty, was led away in chains, and never again did a descendant of David sit on the royal throne. Instead, the people of Israel went on to suffer a long period of outside domination by one foreign ruler after the next. As time went on, people yearned more and more for the restoration of the Davidic kingship and the military and political power that went with it ... The word 'forever' here [in Targum Onkelos] does not correspond to any word in the Hebrew original of this verse. Instead, it represents a conscious attempt by this translator to make sense of an ancient prophecy. Jacob could not have meant that kingship simply would not depart from Judah, not even once, since that had not turned out to be true. The real meaning must therefore have been that it would not depart forever, that sometime it would be restored ..."
Kugel, James L. The Bible as it Was (p. 276) Harvard University Press, 1998