XIX. (63) And it has not fallen to the lot of all the suppliants to become guardians of the holy things, but to those only who have arrived at the number fifty, which proclaims remission of offences and perfect liberty and a return to their ancient possessions. "For this," says the Scripture, "is the law concerning the Levites: from twenty-five years old and upwards, they shall go in to wait upon the service of the tabernacle of the congregation: and from the age of fifty years they shall cease waiting upon the service thereof, and shall serve no more; but shall minister with their brethren in the tabernacle of the congregation, and they shall keep what is to be kept, and shall do no Service."[Nu 8:24.] (64) Therefore, the Scripture charges him who has half perfection (for the number fifty is perfect, and the number twenty-five is the half of fifty), to work and to do what is holy, approving his ministration by his works. And the beginning, as an old writer has said, is half of the whole. But the perfect man it does not enjoin to labour any longer, but only to preserve what he has acquired by labour and diligence. For may I never become a practiser of what I ought not to be a preserve; (65) subsequently practice therefore is mediocrity not perfection, for it takes place not in perfect souls, but in such as are seeking after perfection. But it is the perfect duty of guardianship to deliver to memory the well-practised contemplations of holy things, the excellent deposit of knowledge to a faithful guardian, who is the only one who disregards the ingenious and manifold nets of forgetfulness; so that the Scripture, with great propriety and felicity, calls him who is mindful of what he has learnt, the guardian of it. (66) And such an one before he practised was a pupil, having another to teach him; but when he became competent himself to guard what he had learnt, he then received the power and rank of a teacher, having appointed his brother, his own uttered discourse, to the ministration of teaching. For it is said that, "His brother shall Minister;"[in quoting this passage above, I used the translation as given in the Bible, they "shall minister with their brethren in the tabernacle;" but the Greek of the text was the same in that passage as it is here.] so that the mind of the good man is the guardian and steward of the doctrines of virtue. But his brother, that is to say, uttered discourse, shall minister instead of him, going through all the doctrines and speculations of wisdom to those who are desirous of instruction. (67) On which account Moses, also, in his praises of Levi, having previously said many admirable things, adds subsequently, "He has guarded thy oracles and kept thy Covenant."[De 33:9.] And presently he continues, "They shall show thy justification to Jacob, and thy law to Israel. (68) Therefore, he here clearly asserts that the good man is the guardian of the words and of the covenant of God. And, indeed, in another place he has shown that he is the best interpreter and declarer of his justifications and laws; the faculty of interpretation being displayed through its kindred organ--the voice, and guardianship being exerted through the mind, which having been made by nature as a great storehouse, easily contains the conceptions of all things, whether bodies or things. It would therefore have been worth the while of this self-loving Cain to have been the keeper of Abel; for if he had kept him he would have attained to a compounded and moderate kind of life, and would not have been filled with unmodified and absolute wickedness.