Ezekiel 4:6

And when thou hast accomplished them, lie again on thy right side, and thou shalt bear the iniquity of the house of Judah forty days: I have appointed thee each day for a year.

Cross-reference

In Numbers 14:34, the same 'day for a year' principle is used for the 40-year wilderness wandering, directly mirroring the 40 days assigned here.

Isaiah 20:3 is another prophetic sign-act (Isaiah walking naked for 3 years), matching Ezekiel's 40-day sign as a symbolic action.