=Interpretation.= The significance of the events which took place at Marah, in the wilderness of Sin, and at Rephidim is the same as of those recorded in the preceding chapter. The antagonism felt towards Amalek, which made him the arch-type of all Israel's historic foes, is to be explained by the fact that he was the first to go out of his way to oppose Israel, attacking it where it was weak at a time and in a manner which, because of the lack of any obvious provocation, impressed the Israelites as a direct attempt to defeat God's purpose in having brought them from Egypt. This is suggested by the words, "The hand upon the throne of the Lord; the Lord will have war with Amalek from generation to generation." (Exodus 17. 16.) Thus, Ibn Ezra says in his commentary to Exodus 17. 14, "The reason for God's saying, 41 will utterly blot out the remembrance of Amalek', is because he provoked the Lord, for the dukes of Edom had been terrified with the dread of Him on account of the miracles which He had performed in Egypt and at the Red Sea, and so, too were Moab and Philistia, and behold this Amalek, hearing of the mighty deeds of the Lord in behalf of His people, Israel, came from a distant region to fight with Israel, and dreaded not the Lord, as it is written (Deuteronomy 25. 18), 'and he feared not the Lord'." The incident of the Israelites being victorious, so long as Moses' hands were raised, is to be explained as the rabbis explain it in the Mishnah (Rosh ha-Shanah III. 8). "Could the hands of Moses in any wise make or break a victory that we are told, 'And it came to pass when Moses held up his hand, that Israel prevailed'? This can only mean to tell us that so long as the Israelites looked upward and subjected their hearts to their Father in heaven, they prevailed, and when not, they fell." The visit of Jethro is recorded as a contrast to the preceding episode. Jethro is the type of the "righteous proselyte" who, seeing God's purpose in exalting Israel, seeks to identify himself with Israel's cause. =Aim.= The aim of this lesson is the same as of the preceding.