A calf is born. A lamb is born. The farmer knows this one is destined for the altar — a firstborn male, dedicated to God from its first breath. What happens in the interval between birth and offering?
Targum Pseudo-Jonathan on Exodus (Exodus 22:29) answers with unexpected gentleness: seven days it shall be suckled by its mother, and on the eighth day thou shalt separate it before Me. Seven full days at the mother's side. Only on the eighth is it taken.
Why the Torah Waits
One practical reason: a calf or lamb that has not nursed for a full week is not yet viable for offering. The Torah refuses sickly sacrifices, and it refuses sacrifices that have not had the chance to become whole animals.
But there is also a tenderness here. Even the animal destined for the altar receives a full week of mothering. The same number seven that governs Shabbat, that governs the cycles of purity, that governs the festivals — it also governs this. Even a firstling owes its first week to its mother's warmth.
The Same Eighth Day as the Covenant
The eighth day is also the day of circumcision (Genesis 17:12). A Jewish son enters the covenant on the eighth day. A firstling animal is separated to God on the eighth day. The number is not coincidence — it is the Torah's marker for the passage from raw birth into consecration.
The Takeaway
Even in the economy of sacrifice, the Torah makes room for the mother. Before anything is given to God, life is given its first chance to be nursed.