Commentaria in Exodum
But Scripture does not always observe this distinction, but sometimes confounds them. Hence some think that by this law the firstborn not only of cattle but of all beasts of burden, namely of horses, mules, camels, had to be offered to God; and Philo teaches this, at the beginning of his book On the Honours of the Priests, where he adds that the firstborn of horses, asses, camels are to be redeemed with a price, and that by divine right; whence some think that they were redeemed for five shekels equally with the firstborn of men. But Scripture expresses nothing of the kind, nor does divine right; nay the firstborn of, for example, a goat or a sheep was not worth five at that time, but only two or three shekels.
I say, therefore, that here only the offering of the firstborn of cattle is prescribed, that is, of sheep, goats and oxen, but not of beasts of burden, namely horses, camels, etc. This is plain: for verse 15 signifies that all these firstborn of beasts, that is, of cattle, were wont to be immolated, and, as the Hebrews have it, sacrificed to God; but the Hebrews could sacrifice only sheep, goats and oxen, not horses, mules, camels, as is plain from Leviticus 1, 2 and 10. Therefore only the firstborn of sheep, goats and oxen were to be offered to God; for they were offered for sacrifice. Add that God ordains of the firstborn of the ass alone, in the following verse, that it be exchanged for a sheep; therefore the firstborn of horses, camels and other beasts of burden He here passed over and excluded. Something might be objected here from verse 15, but I shall resolve that there.
Again, what is said in Numbers 18, 15 might be objected: “Every unclean animal thou shalt cause to be redeemed”; but Abulensis answers well that an unclean animal is there called not that which is such according to its species, as the horse, the camel, etc., but that which is such by accident, namely that is unclean because blind, lame, diseased, so that it cannot be immolated to God, according to the law of Leviticus 22, 22. Hence it follows that only of five animals, namely sheep, ox, goat, man and ass, the firstborn had to be offered to God, as Abulensis teaches. See more in Francis Suarez and Sebastian Barradius, tract On the Purification of the Blessed Virgin.
WHATSOEVER THOU SHALT HAVE OF THE MALE SEX, THOU SHALT CONSECRATE TO THE LORD.—For males are worthier than females.
St. Ambrose, On Cain and Abel, chap. 10: “Of the offspring and births of the mind,” he says, “some are feminine, such as malice, wantonness, luxury, intemperance, and other things of the kind, by which our soul is in a manner enervated; others are masculine, such as chastity, patience, prudence, temperance, fortitude, justice, by which our mind and the flesh itself are strengthened, and raised to perform actively the duties of virtue; and therefore Isaias says: ‘In the womb we have conceived, and have brought forth the spirit of salvation’; he therefore bore and brought forth a male, who poured forth the spirit of salvation.”
13. THE FIRSTBORN OF AN ASS THOU SHALT CHANGE FOR A SHEEP.—“Of an ass,” that is, of a she-ass: for her womb is opened, and ass is both male and female; whence to the paschal lamb is added “male,” as I said chap. 12, verse 5.
You will ask, why did God will the ass, namely the firstborn of the ass, to be offered to Him beyond other beasts of burden, that is, that a sheep should be offered in its stead? Why asses alone, I answer, because so it pleased Him: yet the motive cause seems to have been that the Hebrews in Egypt had almost only oxen, and sheep, and goats of cattle, and asses of beasts of burden (so the Hebrews and Abulensis), whose firstborn God spared, and which themselves brought them safe out of Egypt: and so God required for Himself the firstborn of all these, on a kind of title of compensation, that from those to whom the use of the ass was so familiar, and whose firstborn asses God had preserved, He should henceforth receive the same.
Secondly, God perhaps willed an ass to be given to Himself in order to deter the Hebrews by this means from the worship of Priapus; for an ass was immolated to this Priapus: hence that of Ovid concerning the ass, Fasti, book 1:
A victim pleasing to the Hellespontine god;
and that on account of the asinine genitals and loins, of which the Prophet says: “Whose flesh is as the flesh of asses”; the ass (onos) is so called. But because this stupid animal was unworthy to be immolated to God, God therefore ordered that it be exchanged for a sheep. Thirdly, God would not have the young asses torn from their mother, lest He afflict the mother: for no animal loves its offspring so much as the ass and the ape.
Fourthly, tropologically, St. Gregory, book 27 of the Morals, chap. 15: To change the firstborn of the ass for a sheep, he says, is to convert the beginnings of an unclean life into the simplicity of innocence. So also Rupert.
Note: The Jews are wont to use asses (which in Palestine are swift and strong, like horses) in preference to horses and camels. Hence their princes rode on asses, as is plain from Judges chap. 10, verse 4, and chap. 12, verse 14; whence also Christ, the King of Sion, entered Jerusalem borne on an ass: nay the use of horses, as some hold, or more truly the abundance of horses, was forbidden to the Jews, as is plain from Deuteronomy chap. 17, verse 16; Psalm 71, verse 7; Isaias chap. 2, verse 8, and St. Jerome, Basil and Procopius, writing on Isaias chap. 2, expressly teach it.
And these things gave the Gentiles occasion to feign that asses showed water to the Jews in the desert, and that the Jews worship an ass. The leader of the Gentiles in this was Apion, against whom Josephus writes, book 2, chap. 10. Cornelius Tacitus followed, book 5; Plutarch in the Symposium, book 4, Question 5. Again, because the first Christians came forth from the Jews, the same calumny was passed on to them, as Tertullian reports, Apology chap. 16, of Onocoetes, that is, of the hoofed ass of a certain painter: he had, he says, asses’ ears, was hoofed in one foot, carried a book, and was togaed, with this inscription, The God of the Christians, Onocoetes. The same Cæcilius, in Minucius Felix, throws in the teeth of Octavius. Although this calumny and reproach against the Christians was concocted from the Gnostics; for the Gnostics, as Epiphanius testifies, Heresy 62, said that the Lord Sabaoth has the form of an ass, because it was said and promised: “He shall tie his ass to the vine,” Genesis chap. 49, verse 11. And in Numbers chap. 22 the ass of Balaam stood for the Jews and the people of God; and when God had commanded Josue, chap. 11, verse 6, to hamstring the horses taken from the enemies, He yet commanded the she-asses to be preserved.
BUT IF THOU DO NOT REDEEM IT, THOU SHALT KILL IT.—If the firstborn of the ass is too cheap for you to wish to redeem it at the fixed price, namely a sheep, then you shall not immolate it indeed, but shall behead it, and, the neck being cut, kill it; for this the Hebrew araph signifies, that even so you may have a memorial of the firstborn of Egypt slain for your sake. It is strange that in the Septuagint, for “thou shalt kill,” “thou shalt redeem” is read. For so they have: “But if thou do not change it, thou shalt redeem it”: perhaps they meant, if a sheep, with which the foal of the ass was to be exchanged, were not at hand, then this foal was to be redeemed with the price of a sheep. So St. Ambrose seems to explain, book 2 On Cain, chap. 11; but then the other part of the condition is wanting, namely this: If thou wilt redeem this foal of the ass neither with a sheep nor with the price of a sheep, then thou shalt kill it, as the Hebrew, Chaldee and our Interpreter have it.
AND EVERY FIRSTBORN OF MEN OF THY SONS THOU SHALT REDEEM WITH A PRICE,—with five shekels, as is plain from Numbers chap. 18, verse 16. God willed them, when offered to Him, to be redeemed again. First, that this redemption might renew for them the memory of the redemption of the firstborn when these were delivered from the angel and from death. Secondly, because God had destined the Levites alone for His tabernacle and worship; for otherwise the crowd of priests and ministers of God would have been too great, who would therefore often have been idle, and yet would have had to be maintained by the people: which would have been an enormous burden to the people.
14. TO-MORROW,—in future times: it is a synecdoche.