These chapters of Exodus form a bridge between the exodus event (chs. 13-15) and the giving of the law at Mount Sinai (chs. 20-31). These events prepared Israel for life under the law. Three themes surface here. First, God is jealous to be known as the Provider for His people (Exod 15:22-17:16). God prepared Israel for life under the law by testing their faith, and the level of their dependence upon His providence. But just as God’s test of Abraham had a purpose (see Genesis 22), so too He had an agenda in testing Israel’s faith. By miraculously meeting their needs and protecting them from enemies, He further taught Israel of His character. He provided the people with an objective evaluation of their level of trust in Him and prepared them for obedience to His law as it would be given through their leader, Moses (Exod 15:26). When God thus beckoned Israel to trust Him for water (Exod 15:22-27; 17:1-7), food (Exod 16:1-35), and protection (Exod 17:8-16), He was preparing Israel to become a trusting people—those who would recall His providence for generations (see Psalm 105).
Second, God instructs His people in the ways He wants them to live (Exodus 18). Jethro’s visit to Moses prepared Israel for the law by establishing a leadership organization that would eventually serve as the means for instructing Israel in the Sinai covenant. While the text is informative of the importance of leadership delegation, Jethro’s visit goes far beyond providing Moses with some needed help. Rather, God used Jethro’s advice to configure spiritual leaders in such a way that they would be able to apply the Sinai covenant to the every-day life of the nation (Exod 18:21-23).
Third, God is holy (Exodus 19). The atmosphere at the foot of Mount Sinai was so dreadful that boundaries were to be observed simply to avoid instant death in God’s presence (Exod 19:12). The repetition of the command for the people to keep their distance reveals the severity of the situation for any who came near without divine invitation (Exod 19:20-25). The terrifying scene at Mount Sinai had at least three purposes, to: portray for Israel the absolute holiness of the God who would soon instruct them in covenant living (chs. 20-23); provide Israel with an experiential foundation for the call to be a holy nation (Exod 19:6); and cause Israel to fear Moses as the mediator of the law (Exod 19:9).
These scenes of Exodus have implications for understanding the storyline of Scripture.
(1) In Heb 12:18-24, the author of Hebrews contrasted the image of Israel cowering in fear at the foot of Mount Sinai with the bold access his readers enjoyed as they approached God under the auspices of the new covenant. The author’s point was that through Christ participants in the new covenant enjoyed unique access to God—unknown to the generations of Old Testament saints. Those in the new covenant do not stand afar, fearful of God’s presence (Heb 12:18-18-21). Rather, those in the new covenant enjoy free access to God through Jesus’ blood. Access to God through Christ provides believers in the new covenant resources to obtain grace from God that they might persevere in their present Christian trials (Heb 3:14-16; 7:26-28; 10:19-39).
(2) In Rev 7:9; 15:3-4, John heard heavenly choruses singing lyrics that recalled Moses’ song in Exodus 15. Early in Moses’ song in Exodus 15, he wrote, “The LORD is my strength and my song; He has become my salvation” (Exod 15:2). During the great tribulation, John witnessed an international multitude in heaven crying out, “Salvation belongs to our God, who is seated on the throne, and to the Lamb!” (Rev 7:9). John heard the seven angels holding the bowls of judgement singing the song of Moses and of the Lamb (Rev 15:3-4).