John Calvin Commentary Psalms 74:20

"Have respect unto the covenant; For the dark places of the earth are full of the habitations of violence." — Psalms 74:20 (ASV)

Have regard to your covenant. So that God may be more inclined to show mercy, the prophet reminds Him of the Divine covenant; for indeed, the refuge of the saints, when they found themselves involved in extreme dangers, has always been to hope for deliverance, because God had promised in the covenant He made with them to be a father to them.

From this we learn that the only firm support on which our prayers can rest is that God has adopted us to be His people by His free choice.

From this, it also appears how devilish was the frenzy of that filthy dog Servetus, who was not ashamed to affirm that it is foolish and gross mockery to lay before God His own promises when we are engaged in prayer.

Furthermore, the godly Jews again show us how severely they were afflicted when they declare that violence and oppression were everywhere prevalent, as if all places were the haunts of cutthroats and the dens of robbers.

It is said, the dark places of the earth; for whenever God seems to hide His face, the wicked imagine that whatever wickedness they may commit, they will find, wherever they may be, hiding places to conceal it all.