Charles H. Spurgeon on Psalms 136:10

We have heard of the glory of the world's creation, we are now to praise the Lord for the creation of his favoured nation by their Exodus from Egypt. Because the monarch of Egypt stood in the way of the Lord's gracious purposes it became needful for the Lord to deal with him in justice; but the great design was mercy to Israel, and through Israel mercy to succeeding ages, and to all the world. To him that smote Egypt in their firstborn. The last and greatest of the plagues struck all Egypt to the heart. The sorrow and the terror which it caused throughout the nation it is hardly possible to exaggerate. From king to slave each one was wounded in the most tender point. The joy and hope of every household was struck down in one moment, and each family had its own wailing. The former blows had missed their aim compared with the last; but that "smote Egypt." The Lord's firstborn had been oppressed by Egypt, and at last the Lord fulfilled his threatening, "I will slay thy son, even thy firstborn." Justice lingered but it struck home at last. "For his mercy endureth for ever." Yes, even to the extremity of vengeance upon a whole nation the Lord's mercy to his people endured. He is slow to anger, and judgment is his strange work; but when mercy to men demands severe punishments he will not hold back his hand from the needful surgery. What were all the firstborn of Egypt compared with those divine purposes of mercy to all generations of men which were wrapped up in the deliverance of the elect people? Let us even when the Lord's judgments are abroad in the earth continue to sing of his unfailing grace.

"For evermore his love shall last,

For ever sure, for ever fast."