And you shall say unto them, This is the offering made by fire which you shall offer unto the LORD; two lambs of the first year without spot day by day, for a continual burnt offering.
Read Chapter 28
George Leo Haydock
Lambs. Kids would not suffice. See Exodus xxix. 38. The lambs must not be above a year old. But it is not clear whether they could be offered eight days after their birth, as on other occasions, Exodus xxiii. 19. (Calmet)