Ps 33:20

“There should also be certain bones of the inner person in which the bond of union and harmony of spiritual powers is collected. Just as the bones by their own firmness protect the tenderness of the flesh, so also in the church there are some who through their own constancy are able to carry the infirmities of the weak. And as the bones are joined to each other through articulations by sinews and fastenings that have grown on them, so also would be the bond of charity and peace, which achieves a certain natural junction and union of the spiritual bones in the church of God.”

“"The Lord keeps all their bones: not one of them shall be broken" [Psalm 34:20]: this also, Brethren, let us not receive carnally. Bones are the firm supports of the faithful. For as in flesh our bones give firmness, so in the heart of a Christian it is faith that gives firmness. The patience then which is in faith, is as the bones of the inner man: this is that which cannot be broken. "The Lord keeps all their bones: not one of them shall be broken." If of our Lord God Jesus Christ he had said this, "The Lord keeps all the bones of His Son; not one of them shall be broken;" as is prefigured of Him also in another place, when the lamb was spoken of that should be slain, and it was said of it, "Neither shall you break a bone thereof:" [Exodus 12:46] then was it fulfilled in the Lord, because when He hung upon the Cross, He expired before they came to the Cross, and found His Body lifeless already, and would not break His legs, that it might be fulfilled which was written. [John 19:33] But He gave this promise to other Christians also, "The Lord keeps all their bones; not one of them shall be broken." Therefore, Brethren, if we see any Saint suffer tribulation, and haply either by a Physician so cut, or by some persecutor so mangled, that his bones be broken; let us not say, This man was not righteous, for this has the Lord promised to His righteous, of whom He said, "The Lord keeps all their bones; not one of them shall be broken." Would you see that He spoke of other bones, those which we called the firm supports of faith, that is, patience and endurance in all tribulations? For these are the bones which are not broken. Hear, and see ye in the very Passion of our Lord, what I say. The Lord was in the middle Crucified; near Him were two thieves: the one mocked, the other believed: the one was condemned, the other justified: the one had his punishment both in this world, and that which shall be, but unto the other said the Lord, "Verily I say unto you, Today shall you be with Me in Paradise;" [Luke 23:43] and yet those who came broke not the bones of the Lord, but of the thieves they broke: as much were broken the bones of the thief who blasphemed, as of the thief who believed. Where then is that which is spoken, "The Lord keeps all their bones; not one of them shall be broken"? Lo, unto whom He said, "Today shall you be with Me in Paradise," could He keep all his bones? The Lord answers you: Yea, I kept them: for the firm support of his faith could not be broken by those blows whereby his legs were broken.”

“Then when he says, "The Lord guards," he shows how he delivers them so that they do not succumb. He says therefore, "The Lord guards all their bones." Just as sight resides in the eye, so in the bones and sinews resides strength; and therefore, just as sight is signified by the eye, so strength and power are signified by the bones: because just as the body is sustained by bones, so human life is sustained by virtues. In the future, therefore, he will deliver completely, but in the meantime he guards the bones, that is, the virtues, which profit more in weakness. Or, by "bones" are understood the perfect men, whom the Lord will guard: Ezek. 37: "Thus says the Lord God to these bones: Behold, I will send the spirit into you, and you shall live, and I will lay flesh upon you." "Not one of them shall be broken," because in tribulations no virtue of a person fails whom God guards. For charity did not fail in the saints through hatred, because they prayed for their persecutors; not meekness through anger, because no murmur resounded; not patience through injustice, indeed in their patience they possessed their souls. And therefore it is said of the paschal lamb, "You shall not break a bone of it," Ex. 12. Ps. 36: "When he falls, he shall not be dashed." Or, "Not one of these," namely of the predestined. Jn. 17: "None of them has perished except the son of perdition."”