Simply out of gratitude, we can never forget Christ’s great sacrifice on the Cross in saving us from our sins, so that we might live eternally. In the Old Testament, there are many different prophecies and types of the Cross, like the account in Exodus 15 presented in this episode. After Israel’s miraculous deliverance through the Red Sea, they enter a barren wilderness, endure three days without water, and then discover the bitter, undrinkable waters of Marah, causing the people to murmur in unbelief. God instructs Moses to cast a tree into the waters, which instantly transforms them from bitter and poisonous to sweet and life-giving, picturing how Christ’s crucifixion on a tree (the Cross) fully paid the penalty of sin and death, and turned doom into eternal life and blessing.