Does the Universalist interpretation of 1 Cor. 15:28 contradict Luke 1:33 (where the angel Gabriel said “of His kingdom there shall be no end”)?
Is there anything in the underlying Greek text (of either verse) that could remove the problem?
I understand it this way, while God’s kingdom will never end, there is an end to rule and authority, while the kingdom prevails, auhority and harsh rule will one day no longer be needed.
I don’t understand what you mean by this bing a problem for UR.
Lk.1.33 "And He will reign over the house of Jacob forever, and of His kingdom there will be no end.”
1 Cor. 15.28 “Now when all things are made subject to Him, then the Son Himself will also be subject to Him who put all things under Him, that God may be all in all.”
The kingdom does not “end”, though in 15.28 it has a slight change in management, though not really a change if the Son and the Father are one, with the Son having done the will of the Father all along.