Exodus 34:20

20 The firstborn of a donkey you shall redeem with a lamb, or if you will not redeem it you shall break its neck. All the firstborn of your sons you shall redeem. No one shall appear before me empty-handed.

Exodus 34:20 Meaning and Commentary

Exodus 34:20

Every firstling of an ass thou shalt redeem
This goes along with the former, (See Gill on Exodus 13:13):

and none shall appear before me empty;
at the grand festivals, the passover, pentecost, and tabernacles, (See Gill on Exodus 13:15).

Exodus 34:20 In-Context

18 You shall keep the festival of unleavened bread. Seven days you shall eat unleavened bread, as I commanded you, at the time appointed in the month of Abib; for in the month of Abib you came out from Egypt.
19 All that first opens the womb is mine, all your male livestock, the firstborn of cow and sheep.
20 The firstborn of a donkey you shall redeem with a lamb, or if you will not redeem it you shall break its neck. All the firstborn of your sons you shall redeem. No one shall appear before me empty-handed.
21 Six days you shall work, but on the seventh day you shall rest; even in plowing time and in harvest time you shall rest.
22 You shall observe the festival of weeks, the first fruits of wheat harvest, and the festival of ingathering at the turn of the year.