Charles H. Spurgeon on Psalms 34:21

Evil. Afflictions though in the plural, prove not ruinous to the righteous, for the Lord delivers him out of them all, whereas evil in the singular slays the wicked, to signify the difference of God's economy towards righteous and wicked men. The former is permitted to fall into many pressures, the latter is not so frequently exercised with them, yet the many that befall the one do no hurt, but work good for him, whereas the few that befall the wicked, or perhaps the one singular affliction of his life is the utter ruin of him. Henry Hammond.