Isa 5:20 Woe unto them that call evil good, and good evil; that put darkness for light, and light for darkness; that put bitter for sweet, and sweet for bitter!
This is the 4th Class of sins denounced by the prophet Isaiah. It is the sin of’perverting and confounding’things especially distinction in Morality and Religion. They prefer erroneous and fake teachings to the true, they prefer evil to an upright course of conduct.
That is, They say to the impious – “You are good.” They say to the meek, you are evil. They call darkness – just ignorance or error, false teaching. Light speaks to us of the Truth, knowledge and piety.
that put bitter for sweet, and sweet for bitter!
Bitterness speaks of sin and resentment.
Rom 3:14 Whose mouth is full of cursing and bitterness:
Rom 3:15 Their feet are swift to shed blood;
Rom 3:16 Destruction and misery are in their ways;
Eph 4:31 Let all bitterness, and wrath, and anger, and clamor, and railing, be put away from you, with all malice:
Heb 12:15 looking carefully lest there be any man that falls short of the grace of God; lest any root of bitterness springing up trouble you, and thereby the many be defiled;
Lest any root of bitterness springing up – Any bitter root. There is doubtless an allusion here to Deu_29:18. “Lest there should be among you man, or woman, or family, or tribe, whose heart turneth away this day from the Lord our God, to go and serve the gods of these nations; lest there should be among you a root that beareth gall and wormwood.” The allusion there is to those who were idolaters, and who instead of bearing the fruits of righteousness, and promoting the piety and happiness of the nation, would bear the fruits of idolatry, and spread abroad irreligion and sin. The allusion, in both cases, is to a bitter plant springing up among those that were cultivated for ornament or use, or to a tree bearing bitter and poisonous fruit, among those that produced good fruit. The reference of the apostle is to some person who should produce a similar effect in the church – to one who should inculcate false doctrines; or who should apostatise; or who should lead an unholy life, and thus be the means of corrupting and destroying others. They were to be at especial pains that no such person should start up from among themselves, or be tolerated by them.
Trouble you – By his doctrines and example.
And thereby many be defiled – Led away from the faith and corrupted. One wicked man, and especially one hypocrite in the church, may be the means of destroying many others.