What does Exodus 12:3 mean?
The phrase "congregation of Israel" is used to mean every person in the entire nation (Leviticus 4:13; Numbers 16:9). This chapter records the first Passover (Exodus 12:13), a defining moment in the history of Israel. It makes sense, then, that four uses of that Hebrew phrase are found in this chapter (Exodus 12:6, 19, 47). Here, the Lord provides instructions about this crucial night and how Israelites can avoid the devastation coming to the Egyptians (Exodus 11:4–6)."This month" refers to Abib, later called Nisan. Israelites used a calendar aligned to cycles of the moon. Nisan occurs around March or April, and Passover happens after the spring equinox. God has indicated that this month will now be considered the first of each new year (Exodus 12:3).
On the tenth day of Nisan, each home is to select a prized lamb (Exodus 12:5) and separate it from the rest of the flock. On the fourteenth day (Exodus 12:6), the lamb is to be sacrificed at twilight: the transition from one day to the next (Genesis 1:5). God will provide further instructions about how this sacrifice should be treated. The imagery of these rituals foreshadows the ministry of Jesus Christ, who would be the perfect Passover Lamb for all of mankind (John 1:29, 36; Acts 8:32; 1 Corinthians 5:7; 1 Peter 1:19).