We might say that the Psalmist reminds himself of his baptism. Baptism is the seal of the God who is a water brook, the God who slakes our thirst, the Rock of Israel who gave water in the wilderness. Baptism is a promise in water that God will never leave us to dry up in the desert. Baptism is the currency of the marketplace where God offers waters to everyone who thirsts. Hope in baptism is hope in God, the God whose life bursts out always and again like a flower springing from dry ground. ( Peter J. Leithart » Blog Archive » Baptismal meditation)