2 Timothy 2:11-13 (RSVCE) has:
The saying is sure:
If we have died with him, we shall also live with him;
if we endure, we shall also reign with him;
if we deny him, he also will deny us;
if we are faithless, he remains faithful— for he cannot deny himself.
What is the Catholic understanding of 'we shall also reign with him'?
One difficulty, if all reign, who are the subjects?
One Protestant perspective is the thinking that the subjects would be the people in the Millennial Rule of Christ; the ones that were not raptured or survived through the tribulation. Also a thought is that people would still have families and offspring born of them during that time.
'Let them be masters ...' [Gn 1:26]; Joseph and Potiphar Genesis 39:8-9 (RSVCE); 31 and he has filled him with the Spirit of God, with skill, with intelligence, with knowledge, and with all craftsmanship, 32 to devise artistic designs, to work in gold and silver and bronze, [Exodus 35:31-32 (RSVCE)]; David's Adminstration[1 Chronicles 18: 14-17]; 'Truly, I tell you, he will set him over all his possessions.' [cf. Lk 12:44]; The Parable of Talents; you who have followed me will also sit on twelve thrones, judging the twelve tribes of Israel (Matthew 19:28 (RSVCE), 'I came that they may have life, and have it abundantly.' [John 10:10 (RSVCE)], etc.
Also Kings Pele, Elvis, etc.
Filling the stations abandoned by the fallen angels?
King of kings; All nations shall serve and obey him (nations continue?); you are royal priesthood