The last of the seven days of the Festival of Matzot (Unleavened Bread) commemorates ancient Israel’s crossing of the Red Sea, when Heaven delivered not just from slavery but also from certain death at the hands of the slave masters who pursued them.
Apostle Paul connected Israel’s passing from death to life through the sea to the passage of everyone who does likewise by trusting in Yeshua the Messiah (Jesus the Christ) and commemorating the freedom through baptism.