Numbers 10:10-11

10:10 Also in the day of your gladness, and in your solemn days, and in the beginnings of your months, ye shall blow with the trumpets over your burnt offerings, and over the sacrifices of your peace offerings; that they may be to you for a memorial before your God: I [am] the LORD your God. 10:11 And it came to pass on the twentieth [day] of the second month, in the second year, that the cloud was taken up from off the tabernacle of the testimony.