John Calvin Commentary Acts 8:23

"For I see that thou art in the gall of bitterness and in the bond of iniquity." — Acts 8:23 (ASV)

In the gall of bitterness. Peter sharply reproves Simon again and strikes him with God’s judgment. For unless he had been compelled to look inward, he would never have turned earnestly to God. For there is nothing more deadly for men who are dull than when we flatter them, or when we only scratch the surface, when instead they ought to be pierced through.

Therefore, until a sinner conceives sorrow and true grief because of his sin, we must use such severity as will wound his mind; otherwise, the rotten sore will be nourished within, which will gradually consume the man himself. Yet let us always observe this balance: that we provide for men’s salvation as much as lies in our power.

Moreover, there are two very fine metaphors in Peter’s words, one of which seems to be taken from Moses, where he forbids that there be in us any root from which springs gall and wormwood (Deuteronomy 29). By this expression, the inward wickedness of the heart is noted; when it has so conceived the poison of ungodliness, that being infected with it, it can produce nothing but bitterness.

The binding of iniquity tends to the same end: that is, when the whole heart is kept bound and tied by Satan. For it sometimes happens that men who are otherwise very godly break out into evil works, whose hearts are not inwardly corrupt with poison. We know that hypocrisy is engendered in human nature; but when the Spirit of God shines, we are so blinded by our vices that we nourish them within as if they were some hidden bundle.

Therefore, Peter’s meaning is that Simon not only fell in one point, but that the very root of his heart was corrupt and bitter; that he fell into Satan’s snares not only in one kind of sin, but that all his senses were ensnared, so that he was wholly given over to Satan, and had become the bondslave of iniquity. Meanwhile, we are taught that the greatness of offenses is judged not so much according to the outward act as according to the disposition of the heart.