Charles H. Spurgeon on Psalms 136:18

And slew famous kings. What good was their fame to them? As they opposed God they became infamous rather than famous. Their deaths made the Lord's fame to increase among the nations while their fame ended in disgraceful defeat. For his mercy endureth for ever. Israelitish patriots felt that they, could never have too much of this music; God had protected their nation, and they chanted his praises with unwearied iteration.

Kings he smote despite their fame,

For his mercy's still the same.