while they were reclining: the Passover meal was eaten while reclining, as was common at banquet meals. During the meal, someone (usually the youngest son) would ask the host, “Why is this night different from other nights?” The father or host would then tell the stories of the Passover and the exodus from Egypt (Deuteronomy 26:5–9).
The foods in the Passover meal had symbolic meaning:
The Passover lamb reminded the people of the blood of the sacrificial lambs that protected Israelite homes from the angel of death in Egypt (Exodus 12:28–30).
The unleavened bread reminded them of the Israelites’ quick departure from Egypt (Exodus 12:31–34, 39).
The salt water represented both the tears of slavery and the crossing of the Red Sea. The bitter herbs represented the bitterness of slavery.
The four cups of wine recalled God’s fourfold promise in Exodus 6:6–7.
The betrayal of Jesus was especially terrible because the betrayer was one of those eating with him (see Psalms 41:9; 55:12–14).