The Crossing of the Sea is a central part of the Passover story and is symbolized by the recitation of the Song of the Sea, which is a hymn of praise and gratitude to God for the Israelites' salvation at the sea.
According to the Biblical account in the Book of Exodus, after Moses asked Pharaoh to release the Israelites from slavery, Pharaoh refused, and God sent ten plagues upon Egypt. After the final plague, which was the death of the firstborn, Pharaoh agreed to let the Israelites go, but then changed his mind and pursued them with his army.
At the shore of the Red Sea, Moses was instructed by God to stretch out his hand, and the waters of the sea were miraculously parted, forming a wall on either side, allowing the Israelites to pass through on dry land. Once the Israelites had safely crossed, the waters returned to their original state, drowning the pursuing Egyptian army.
The crossing of the sea is considered a significant event in Jewish history and is recited both as part of the Seder on the first night of Passover, and again as the Torah reading during the seventh day’s morning services. The story of the crossing of the sea represents the miraculous redemption of the Israelites from slavery in Egypt and the beginning of their journey towards the Promised Land.