Only three days after the Red Sea, Israel found no water. At Marah the water was bitter, and the people complained. Moses cried out to the LORD, and the LORD showed him a tree; when he cast it into the waters, the waters were made sweet. There God revealed Himself with a new name: “For I am the LORD who heals you.” Then He led them to Elim, where there were twelve wells of water and seventy palm trees.
In the Wilderness of Sin the people grumbled for food, remembering the pots of meat in Egypt. God answered with grace: “Behold, I will rain bread from heaven for you.” Each morning a small, round substance lay on the ground. The people said, “What is it?” — in Hebrew, manna. Moses said, “This is the bread which the LORD has given you to eat.” They gathered enough for each day, and a double portion before the Sabbath. Jesus would later say, “I am the bread of life.”
At Rephidim there was again no water, and the people quarreled with Moses. God told him to strike the rock at Horeb, and water came out for the people to drink. Paul later wrote that they “drank of that spiritual Rock that followed them, and that Rock was Christ.” God provided for Israel not because they were patient, but because He is faithful.
Then Amalek came and fought against Israel. Joshua led the battle while Moses stood on the hill with the rod of God. “When Moses held up his hand, Israel prevailed; and when he let down his hand, Amalek prevailed.” When Moses grew tired, Aaron and Hur held up his hands, one on each side, until the sun went down. Moses built an altar and called it The-LORD-Is-My-Banner.