In Exodus 15:22–27, Israel’s quick turn from praise to grumbling in the wilderness reveals the deeper danger of the Christian life: not external enemies, but the sinful tendency of the heart to doubt God’s goodness when trials come. Their bitter waters at Marah expose both the reality of suffering and the temptation to respond with grumbling rather than lament. Yet God provides a remedy when he shows Moses a tree that turns the bitter water sweet, pointing forward to the greater “tree” of the cross, where Christ entered our bitterness, bore our curse, and turned the waters of death and sorrow into sweetness for his people.

The song of Exodus 15 is the first congregational song in all of Scripture — and they had good reason to sing, having just beheld their salvation! We, as Christians, have the best possible reason to sing praise to God and the firmest hope. Singing together is a Christian privilege, as we follow our Worship Leader (Jesus) in joining heaven’s song.

From Israel’s desperate moment at the Red Sea, this sermon highlights that salvation is entirely God’s work from start to finish: he takes the initiative, he fights the battle, and he brings his people through from death to life. The crossing is portrayed as a new-creation event—dark waters divided, dry land appearing—showing that just as God created the world without help, so he saves sinners by sheer grace. Israel contributed nothing but need; they were told to be still and see the Lord’s salvation. Yet grace does not eliminate response: salvation is by grace alone, through faith alone. Faith is not vague sentiment but active trust—stepping into the path God opens, abandoning all self-made “rafts,” repenting daily, and living in light of Christ’s promises. Because God fights first and wins, believers can stop trying to earn rescue and instead follow Jesus confidently, even when obedience feels like death, trusting him for resurrection life on the other side.