Thomas Aquinas, on Heb 12:11

“Now all chastisement for the present indeed seemeth not to bring with it joy, but sorrow: but afterwards it will yield, to them that are exercised by it, the most peaceable fruit of justice.”

“681. – He continues: All discipline [chastisement] seems painful rather than pleasant; later it yields the peaceful fruit of righteousness [justice] to those who have been trained by it. This is the third reason, which is drawn from the benefit of the correction. But since chastisements are forms of medicine, the same judgement seems to be true of chastisement as of medicine. But just as medicine, when it is taken, is bitter and disgusting, and yet its end is very sweet and desirable, so chastisement, although it is harder to endure, brings forth the best fruit. But it should be noted that chastisement, i.e., discipline, is drawn from the word 'to learn.' But children, who are taught, learn from the rod. Therefore, discipline is taken for science, as in the beginning of Posterior Analytics: 'Every intellectual doctrine and discipline comes into existence from pre-existing knowledge,' which in Greek is called epistemon. But sometimes it is taken for correction, which in Greek is paideia. He says, therefore: All chastisement, which is instruction by blows and annoyances, for the moment, indeed, seems painful rather than pleasant; because outwardly it brings sadness in enduring it, but inwardly it brings sweetness because of the end intended. Hence he says, seems and not 'is': 'As sad and always rejoicing' (2 Cor. 6:10); 'A woman, when in labor, is sorrowful; but when she has brought forth, she no longer remembers the anguish, for her joy' (Jn. 16:21); 'That which is at present momentary and light of our tribulation works for us above measure exceedingly an eternal weight of glory' (2 Cor. 4:17). 682. – Therefore, he says, later it yields fruit, for fruit implies sweetness: hence, fruition is delight in the end now achieved. Most peaceful, for fruit is had here with disturbance of external inconveniences and internal trials; therefore, it is not most peaceful, as there. In glory, indeed, there will be no inward gnawing of conscience, no inclination to sin, no outward affliction. For according to Augustine, whatever you desire will be there; therefore, the fruit will be most peaceful: peaceful in the tranquility of conscience; more peaceful in obtaining the first stole; most peaceful in obtaining the second: 'My people shall sit in the beauty of peace, in the tabernacles of confidence and in wealthy rest' (Is. 32:18); 'Her fruit is better the chiefest and purest gold' (Pr. 3:14). Therefore, it will yield the fruit of righteousness [justice], i.e., which justice earns: 'To him that sows justice there is a faithful reward' (Pr. 11:30). Or of justice, i.e., to lay hold on justice: 'Sow for yourselves in justice and reap in the mouth of mercy' (Hos 10:12); 'Going, they went and wept, sheaves' (Ps. 125:6). But fruit is brought forth only to them that are exercised in it, i.e., by discipline: 'Strong meat is for the perfect; for those who by custom have their senses exercised' (Heb. 5:14).”

Imported from an open dataset — not yet checked against the printed edition.