# Do you not remember ... these things?

Paul uses a rhetorical question to remind them of his teaching when he was with them previously. This can be expressed as a statement. AT: "I am sure you remember ... these things." (See: [[rc://en/ta/man/translate/figs-rquestion]])

# these things

This refers to the return of Jesus, the day of the Lord, and the man of lawlessness.

# he will be revealed only at the right time

This can be stated in active form. AT: "God will reveal the man of lawlessness when the time is right" (See: [[rc://en/ta/man/translate/figs-activepassive]])

# mystery of lawlessness

This refers to a sacred secret that only God knows.

# who restrains him

To restrain someone is to hold them back or to keep them from doing what they want to do.