Numbers 28:29

And the LORD spake unto Moses, saying,

Command the children of Israel, and say unto them, My offering, and my bread for my sacrifices made by fire, for a sweet savour unto me, shall ye observe to offer unto me in their due season.

And thou shalt say unto them, This is the offering made by fire which ye shall offer unto the LORD; two lambs of the first year without spot day by day, for a continual burnt offering.

The one lamb shalt thou offer in the morning, and the other lamb shalt thou offer at even;