en_tn/luk/21/33.md

Heaven and earth will pass away

"Heaven and earth will cease to exist." The word "heaven" here refers to the sky and the universe beyond it.

my words will never pass away

"my words will never cease to exist" or "my words will never fail." Jesus uses "words" here to refer to everything he says. (See: rc://en/ta/man/jit/figs-metonymy)

will never pass away

This could be stated in positive form. Alternate translation: "will remain forever"