Charles H. Spurgeon on Psalms 54:5

He shall reward evil unto mine enemies. They worked for evil, and they shall have their wages. It cannot be that malice should go unavenged. It were cruelty to the good to be lenient to their persecutors. It is appointed, and so it must ever be, that those who shoot upward the arrows of malice shall find them fall upon themselves. The recoil of their own gun has often killed oppressors. Cut them off in thy truth. Not in ferocious revenge is this spoken, but as an Amen to the sure sentence of the just Judge. Let the veracity of thy threatenings be placed beyond dispute, the decree is right and just, let it be fulfilled. It is not a private desire, but the solemn utterance of a military man, a grossly injured man, a public leader destined to be a monarch, and a man well trained in the school of Moses, whose law ordains eye for eye, and tooth for tooth.