Exodus 12:5

Without blemish. Freedom from blemish and injury not only befitted the sacredness of the purpose to which the animals were to be devoted, but was a symbol of the moral integrity of the One represented by the sacrifice. A devout spirit would teach a man that the “blind,” the “lame,” and the “sick” would not be acceptable to God (Mal. 1:8). The law afterward expressly prohibited the use of imperfect animals for obligatory sacrifices, though they might be presented as freewill offerings (Lev. 22:20-25). Freedom from blemish was especially important in a victim intended to typify Christ.

A male. This requirement was made because the lamb stood in the place of the first-born male of the family.

Of the first year. The animals to be selected were probably older than 7 days (see Ex. 22:30; Lev. 22:27), but should not in any case exceed the age of 12 months.