Ps 103:18

“What then followeth? "The loftiest hills are for the stags" (ver. 18). The stags are mighty, spiritual, passing in their course over all the thorny places of the thickets and woods. "He maketh my feet like harts' feet, and setteth me up on high." Let them hold to the lofty hills, the lofty commandments of God; let them think on sublime subjects, let them hold those which stand forth most in the Scriptures, let them be justified in the highest: for those loftiest hills are for the stags. What of the humble beasts? what of the hare? what of the hedgehog? The hare is a small and weak animal: the hedgehog is also prickly: the one is a timid animal, the other is covered with prickles. What do the prickles signify, except sinners? He who sinneth daily, although not great sins, is covered over with the smallest prickles. In his timidity he is a hare: in his being covered with the minutest sins, he is a hedgehog: and he cannot hold those lofty and perfect commandments. For "the loftiest hills are for the stags." What then? do these perish? No. For so "is the rock the refuge for the hedgehogs and the hares." For the Lord is a refuge for the poor. Place that rock upon the land, it is a refuge for hedgehogs, and for hares: place it on the sea, it is the home of the coot. Everywhere the rock is useful. Even in the hills it is useful: for the hills without the rock's foundation would fall into the deep. ...”

“And so by the illumination of God himself he mounts to that manifold knowledge of him and begins to be nourished on more sublime and still more sacred mysteries, in accordance with these words of the prophet: "The high hills are a refuge for the stags, the rocks for the hedgehogs," which is fairly applied in the sense we have given, because whoever continues in simplicity and innocence is not harmful or offensive to any one, but being content with his own simple condition endeavors simply to defend himself from being harmed by his foes and becomes a sort of spiritual hedgehog, protected by the continual shield of that rock of the gospel. That is, while he is sheltered by the recollection of the Lord's passion and by ceaseless meditation on the verse given above, he escapes the snares of his enemies. And of these spiritual hedgehogs we read in Proverbs as follows: "And the hedgehogs are a feeble folk, who have made their homes in the rocks."”