Luke 9:36

Revised Standard Version (RSV-CI)

And when the voice had spoken, Jesus was found alone. And they kept silence and told no one in those days anything of what they had seen.

See the chapter Copy

a time to rend, and a time to sew; a time to keep silence, and a time to speak;

And as they were coming down the mountain, Jesus commanded them, “Tell no one the vision, until the Son of man is raised from the dead.”

For he did not know what to say, for they were exceedingly afraid.