From the early Church Fathers to now.
3 Patristic · 1 Medieval
“He that keepeth the commandments shall find no evil. The heart of a wise man understandeth time and answer.”
“And you find in another passage, "For he that keeps the commandment does not know the wicked word" when it is altogether clear that knowledge of wickedness is not culpable, but association with it is.”
“Whoever knows what is good also knows at the same time what is bad. "To know" here does not mean "to do" but simply "to know about something." Because when the commandment is given to turn away from evil and do good, we must also know evil in order to be able to turn away from it and to choose good. About these things the apostle writes with the following words: "But test everything; hold fast to what is good; abstain from every form of evil." One sees here that whoever tests everything, knows that the good is to be chosen and obeyed and that the evil is to be avoided.… Ecclesiastes means that he who obeys the command does not know an evil word, that is, he does not say that he does not "understand" it, but that he does not "use" it.”
“"He who obeys the commandment will know no evil; and a wise man will know time and justice. "Notice here in particular that 'he will know no evil' has been written instead of 'he will not suffer' or even 'evil will not be in him'. Likewise it has also been written about the Saviour, "for he has made him to be sin for us, who knew no sin." [II Cor. 5, 21.] Instead of 'evil' too Symmachus interprets this phrase as saying, "he who keeps the commandment will experience no wickedness". But he teaches that we should keep the command of a king, and know why and when he orders.”
“Here he thirdly exhorts us to cling to wisdom by consideration of our benefit. For there is great benefit in clinging to it and keeping its commandments. On account of which he says: He who keeps the commandment shall experience nothing evil: indeed he shall have many good things: Matthew 19: "If you wish to enter into life, keep the commandments"; and John 8: "If you abide in my word, you shall truly be my disciples, and you shall know the truth, and the truth shall set you free." Here he fourthly exhorts us to keep the commandments of divine wisdom by consideration of the opportunity of time, which the wise man considers in his works. On account of which he says: The heart of the wise man understands the time and the response: he understands the time in which one ought to act: Ephesians 5: "See, brethren, how carefully you walk, not as unwise, but as wise, redeeming the time, because the days are evil." Not only the time, but also the response in its time: Colossians 4: "Walk in wisdom toward those who are outside, redeeming the time. Let your speech always be with grace, seasoned with salt, that you may know how you ought to respond to each one." There is also a doubt about this, because he says: He who keeps the commandment will not experience anything evil. Against this: below in the same chapter: There are just men to whom evils befall as though they had done the works of the wicked. I respond: there is experiencing evil that endures and evil that passes away; and he speaks here of the experience of evil that always remains, not of that which passes away. There is also a question about what he says: He who keeps the commandment, etc. 1. Since there are many commandments to be kept, why does he say "commandment" in the singular? 2. Furthermore, it is possible for someone to keep the divine commandments out of fear, as the Jews kept them; and yet such persons are not saved. I respond: it must be said that although the commandments are many by diversity of work, nevertheless they have unity both in relation to the one commanding, and in relation to the one observing, and in relation to the end. In relation to the one commanding, because he who commands is one; and therefore whoever transgresses one commandment cannot be obedient to the one commanding, because the one who commands is one. — In relation to the one observing there is unity, because he observes all things by one principle and rule, namely charity, which conquers all things. Whence, just as charity either loves all or none, so it observes all commandments or none. In relation to the end there is unity, because one reward is owed, and they are to be observed for one reward. Because therefore this threefold unity concurs in the due observance of the commandments, he rightly says: He who keeps the commandment, etc.”
The in-app commentary runs from the Fathers to the early-modern record, then stops — that's where the public-domain sources end, not where the reading does. For the modern reading, follow the sources directly.