15:22–26 With Pharaoh’s forces defeated (14:26–29) Moses now leads the Israelites away from the Red Sea (cf. note 264 within comment on 13:17–22). They travel to the Wilderness of Shur (15:22), which is east of Egypt and known also as the “wilderness of Etham” (Num. 33:8). After a three-day journey, they have not found water. Traveling farther, they find water, but it is too bitter to drink, leading them to name the place Marah (Ex. 15:23; in Hebrew “Marah” means “bitter”; cf. Ruth 1:20).

This is a crisis. When water supplies run out in the wilderness, death soon follows. The Israelites could call out in faith, asking the Lord to deliver them from this crisis as he has just delivered them from another (cf. Ex. 14:13–31), but instead they respond again with unbelief (15:24; cf. 14:10–12). The word “grumbling” refers to a strong expression of discontent with the Lord or his leaders (cf. 16:2–3, 7; 17:3; Num. 14:2, 27, 29; 16:41). Faced with their response, Moses cries out to the Lord for help, and the Lord provides a solution: he shows Moses a log to throw into the waters that will make them drinkable (Ex. 15:25).

While some have explained this by noting that certain types of wood have natural properties that make bitter waters drinkable,293 no such wood has been identified in the Sinai region, nor is it clear that a single log with such properties could purify the large amount of water needed for the people. It is far more likely that this is a miracle—the Lord himself has again rescued Israel. In doing so he provides an object lesson: just as the Lord is the one who has “healed” the water (v. 25), he is the one who “heals” Israel (v. 26; cf. Deut. 32:39).294 Indeed, while he mentions his discipline (“I will put none of the diseases on you that I put on the Egyptians”), he focuses on his love for his people (“for I am the Lord, your healer”). He leans toward them with care, not judgment.

But this does not mean the Israelites can live any way they like. The Lord provides “a statute and rule” by which he will “test” them (Ex. 15:25). In the singular the language of “statute and rule” often refers to a binding custom or law (Num. 9:14; 27:11; 1 Sam. 30:25). In this case the “statute and rule” is that, if Israel is faithful to the Lord, then he will protect them from harm and bless them with good (Ex. 15:26). This is a “test” insofar as it establishes a standard of behavior by which Israel will be measured, namely, obedience to their covenant king (cf. also the use of “test” in Ex. 16:4; Deut. 8:2; 13:3; Judg. 2:22; 3:4).

It may be noted that the Pentateuch frequently emphasizes the importance of Israel’s continued faithfulness to the covenant in order to experience the Lord’s covenant blessings (Lev. 26:3–12; Deut. 4:1; 5:31–33; 26:16–19; 30:16). Deuteronomy 7:11–16 even appears to look back to Exodus 15:26 when it states that one sign of the Lord’s blessing for Israel’s faithfulness is his healing of diseases that the Israelites knew in Egypt (Deut. 7:15). But it would be wrong to think their obedience somehow earns his love. As I wrote elsewhere on a related verse (Lev. 18:5), the Israelites were not

in some way earning the Lord’s salvific favor. As the larger context demonstrates, redemption (Ex. 1–19) comes before law (Ex. 20–23). Or, to put it the other way, “The law was given to the covenant people after their redemption from Egypt (Lev. 18:3), not as a moral hurdle they had to clear if they wished to be saved.”

What, then, is the relationship between [obedience] and [blessing]? God’s law may be thought of as marking the borders of his kingdom or the borders of the fields in which he walks. Those who stay within the borders stay close to the King, maintaining fellowship with him and experiencing the blessings he loves to give to his faithful children. As Jesus said to his disciples, “If you keep my commandments, you will remain in my love, just as I have kept my Father’s commandments and remain in his love” (John 15:10; see also John 14:21). Obedience is not about earning God’s love but about remaining in his love and experiencing its rich rewards. Put differently, the Lord is a King who rescues out of sheer love and who delights to shower that love in blessings and rewards on his faithful children.295

In short this is a king who saves his servants in sheer love and then loves to reward their faithful service with good things.

15:27 As though to underscore how the Lord shows his care, the text mentions the Israelites’ arrival at Elim, “where there were twelve springs of water,” enough to provide one spring for each tribe, “and seventy palm trees,” with the number seventy having connotations of fullness and plenty (cf. note 56 within comment on 1:1–5). Even in the wilderness the Israelites can obey the Lord with full trust, knowing that he can provide abundantly for their needs.