"in the new time." This refers to when God restores all things. AT: "at the time when God makes all things new" (See: [[rc://en/ta/man/translate/figs-metonymy]])
Jesus is speaking about himself. (See: [[rc://en/ta/man/translate/figs-123person]])
# sits on his glorious throne
Sitting on his throne represents ruling as a king. His throne being glorious represents his rule being glorious. AT: "sits as king on his glorious throne" or "rules gloriously as king" (See: [[rc://en/ta/man/translate/figs-metonymy]])
# sit upon twelve thrones
Here "thrones" refers to ruling as king. The disciples will not be equal to Jesus who is also on a throne. They will receive authority from him. AT: "sit as kings on 12 thrones" (See: [[rc://en/ta/man/translate/figs-metonymy]])
# the twelve tribes of Israel
Here "tribes" refers to people from those tribes. AT: "the people of the 12 tribes of Israel" (See: [[rc://en/ta/man/translate/figs-metonymy]])