7 “By Your chiding, O God of Jacob, there have slept all men that have mounted horses”. Who are they that have mounted horses? They that would not be humble. To sit on horseback is no sin; but it is a sin to lift up the neck of power against God, and to deem one's self to be in some distinction. Because you are rich, you have mounted; God does chide, and you sleep. Great is the anger of Him chiding, great the anger. Let your Love observe the terrible thing. Chiding has noise, the noise is wont to make men wake.
So great is the force of God chiding, that he said, “By Your chiding, O God of Jacob, there have slept all men that have mounted horses.” Behold what a sleep that Pharaoh slept who mounted horses. For he was not awake in heart, because against chiding he had his heart hardened. For hardness of heart is slumber. I ask you, my brethren, how they sleep, who, while the Gospel is sounding, and the Amen, and the Hallelujah, throughout the whole world, yet will not condemn their old life, and wake up unto a new life.
There was the Scripture of God in Judæa only, now throughout the whole world it is sung. In that one nation one God who made all things was spoken of, as to be adored and worshipped; now where is He unsaid? Christ has risen again, though derided on the Cross; that very Cross whereon He was derided, He has now imprinted on the brows of kings: and men yet sleep....
Source: The Enarrations, or Expositions, on the Psalms (New Advent)