Yechezkel 4:4-5

Lie thou also upon thy left side, and lay the avon Bais Yisroel upon it; according to the mispar of the yamim that thou shalt lie upon it thou shalt bear their avon. For I have laid upon thee the shanim of their avon (iniquity), according to the mispar (number) of the yamim, three hundred and ninety days; so shalt thou bear the avon Bais Yisroel.