John warns his readers
John fell down to worship at the feet of the angel, and he was told not to. Jesus warned the hearers of the prophecy not to add to it or take away from it.
Key passages
Re 22:6–21

And he said to me, “These words are faithful and true, and the Lord, the God of the spirits of the prophets, has sent his angel to show his slaves the things which must take place in a short time.” “And behold, I am coming quickly! Blessed is the one who keeps the …

See also
Important Things