The following enumeration of the "signs" does not follow the order in Exodus, but begins with the ninth plague, perhaps because of its severity, and then in the main adheres to the original sequence, though it inverts the order of the third and forth plagues (flies and gnats or mosquitoes, not "lice") and omits the fifth and sixth. The reason for this divergence is far from clear, but it may be noted that the first two in the psalmist's order attack the elements; the next three (frogs, flies, gnats) have to do with animal life; and the next two (hail and locusts), which embrace both these categories, are considered chiefly as affecting vegetable products. The emphasis is laid in all on God's direct act. _He_ sends darkness, _He_ turns the waters into blood, and so on. The only other point needing notice in these verses is the statement in ver. 28_b_. "They rebelled not against His word," which obviously is true only in reference to Moses and Aaron, who shrank not from their perilous embassage. The tenth plague is briefly told, for the psalm is hurrying on to the triumphant climax of the Exodus, when, enriched with silver and gold, the tribes went forth, strong for their desert march, and Egypt rejoiced to see the last of them, "for they said, We be all dead men" (Exod. xii. 33). There may be a veiled hope in this exultant picture of the Exodus, that present oppression will end in like manner. The wilderness sojourn is so treated in ver. 39 _sqq._ as to bring into sight only the leading instances, sung in many psalms, of God's protection, without one disturbing reference to the sins and failures which darkened the forty years. These are spread out at length, without flattery or minimising, in the next psalm; but here the theme is God's wonders. Therefore, the pillar of cloud which guided, covered, and illumined the camp, the miracles which provided food and water, are touched on in vv. 39-41, and then the psalmist gathers up the lessons which he would teach in three great thoughts. The reason for God's merciful dealings with His people is His remembrance of His covenant, and of His servant Abraham, whose faith made a claim on God, for the fulfilment which would vindicate it. That covenant has been amply fulfilled, for Israel came forth with ringing songs, and took possession of lands which they had not tilled, and houses which they had not built. The purpose of covenant and fulfilment is that the nation, thus admitted into special relations with God, should by His mercies be drawn to keep His commandments, and in obedience find rest and closer fellowship with its God. The psalmist had learned that God gives before He demands or commands, and that "Love," springing from grateful reception of His benefits, "is the fulfilling of the Law." He anticipates the full Christian exhortation, "I beseech you, brethren, by the mercies of God, that ye present your bodies a living sacrifice." PSALM CVI.