Numbers 12:1

Miriam the prophetess herself, who with her brothers had crossed the straits of the sea on foot, because, being still ignorant of the mystery of the Ethiopian woman, she had murmured against her brother Moses, broke out with leprous spots, so that she would scarcely have been freed from so great a plague, unless Moses had prayed for her. Although this murmuring refers to the type of the Synagogue, which is ignorant of the mystery of that Ethiopian woman, that is the Church gathered out of the nations, and murmurs with daily reproaches, and envies that people through whose faith itself also shall be delivered from the leprosy of its unbelief, according to what we read that: "blindness in part has happened unto Israel, until the fulness of the Gentiles be come in, and so all Israel shall be saved."

Aaron and Miriam murmur, because Moses has an Ethiopian woman for a wife. And now Moses takes an Ethiopian woman for a wife, since his law has passed over to this Ethiopian woman of ours. Let Aaron murmur — the priesthood of the Jews; let Miriam also murmur — their Synagogue: Moses cares nothing for the murmuring; he loves his Ethiopian woman, of whom it is also said elsewhere through the Prophet: From the ends of the rivers of Ethiopia they shall bring offerings; and again: Ethiopia shall stretch out her hands to God before others. Beautifully, "before others." For just as, in the Gospel, that woman with the issue of blood anticipated the healing of the synagogue-ruler's daughter, so Ethiopia, while Israel was sick, was healed. By their offense, salvation came to the Gentiles, to provoke them to jealousy.

But in what follows also the reading which was recited contains this, that Moses took the Ethiopian woman as his wife, and that Miriam and Aaron disparaged Moses, because he had taken the Ethiopian woman, and they say: "Has God spoken to Moses alone? Has He not also spoken to us?" "And the Lord heard," it says. And after these things He orders them to go out to the tabernacle of the testimony, and there, a certain judgment having been held, Miriam is made leprous until a fixed time, and thus is called back into the camp. That we may explain this more concisely, we say that Miriam had the figure of the former people, and that Moses, that is, the law of the Lord, passed over to marriage with this Ethiopian woman, who was gathered from among the nations. Her, therefore, Moses, that is, the spiritual law, took as wife; and on account of this deed Miriam, who is now the synagogue, is indignant and disparages together with Aaron, that is, with the priests and Pharisees. That people, therefore, disparages even to this day Moses, who is placed with us, and he seems base to them, because among us he does not teach the circumcision of the flesh, nor the observance of the sabbath, nor of the new moon, nor sacrifices of blood, but the circumcision of the heart, and rest from sinning, and feast days in the unleavened bread of sincerity and truth, and sacrifices of praise, and admonishes that now not victims of cattle, but of vices, should be slain. God therefore judges concerning these things, and confirms the marriage of the Ethiopian woman, and indeed permits Moses gladly to dwell with her and to rest, but casts Miriam outside the camp and puts her far from the tabernacle of the testimony, with whom Aaron also is cast out. Moreover, Miriam is also made leprous. Look now upon that people and see how great in it is the leprosy of sin, how great the darkness of understanding, how great the foulness of observance, how great the baseness of aspect. Nevertheless this leprosy does not remain forever, but when the week of the world shall have begun to be completed, she shall be called back to the camp. For at the end of the world, when the fullness of the nations shall have entered in, then also all Israel shall be saved, and that is when the leprosy shall cease from the face of Miriam; for she shall receive the glory of faith, and shall receive the splendor of the knowledge…