In these verses the apostle puts them in mind of what they were before their conversion to the faith of Christ, and what a blessed change their conversion had made upon them; and thence endeavours to convince them of their great weakness in hearkening to those who would bring them under the bondage of the law of Moses.
I. He reminds them of their past state and behaviour, and what they were before the gospel was preached to them. Then they knew not God; they were grossly ignorant of the true God, and the way wherein he is to be worshipped: and at that time they were under the worst of slaveries, for they did service to those which by nature were no gods, they were employed in a great number of superstitious and idolatrous services to those who, though they were accounted gods, were yet really no gods, but mere creatures, and perhaps of their own making, and therefore were utterly unable to hear and help them. Note, 1. Those who are ignorant of the true God cannot but be inclined to false gods. Those who forsook the God who made the world, rather than be without gods, worshipped such as they themselves made. 2. Religious worship is due to none but to him who is by nature God; for, when the apostle blames the doing service to such as by nature were no gods, he plainly shows that he only who is by nature God is the proper object of our religious worship.
II. He calls upon them to consider the happy change that was made in them by the preaching of the gospel among them. Now they had known God (they were brought to the knowledge of the true God and of his Son Jesus Christ, whereby they were recovered out of the ignorance and bondage under which they before lay) or rather were known of God; this happy change in their state, whereby they were turned from idols to the living God, and through Christ had received the adoption of sons, was not owing to themselves, but to him; it was the effect of his free and rich grace towards them, and as such they ought to account it; and therefore hereby they were laid under the greater obligation to adhere to the liberty wherewith he had made them free. Note, All our acquaintance with God begins with him; we know him, because we are known of him.
III. Hence he infers the unreasonableness and madness of their suffering themselves to be brought again into a state of bondage. He speaks of it with surprise and deep concern of mind that such as they should do so: How turn you again, etc., says he, Gal. 4:9. “How is it that you, who have been taught to worship God in the gospel way, should not be persuaded to comply with the ceremonial way of worship? that you, who have been acquainted with a dispensation of light, liberty, and love, as that of the gospel is, should now submit to a dispensation of darkness, and bondage, and terror, as that of the law is?” This they had the less reason for, since they had never been under the law of Moses, as the Jews had been; and therefore on this account they were more inexcusable than the Jews themselves, who might be supposed to have some fondness for that which had been of such long standing among them. Besides, what they suffered themselves to be brought into bondage to were but weak and beggarly elements, such things as had no power in them to cleanse the soul, nor to afford any solid satisfaction to the mind, and which were only designed for that state of pupillage under which the church had been, but which had now come to a period; and therefore their weakness and folly were the more aggravated, in submitting to them, and in symbolizing with the Jews in observing their various festivals, here signified by days, and months, and times, and years. Here note, 1. It is possible for those who have made great professions of religion to be afterwards drawn into very great defections from the purity and simplicity of it, for this was the case of these Christians. And, 2. The more mercy God has shown to any, in bringing them into an acquaintance with the gospel, and the liberties and privileges of it, the greater are their sin and folly in suffering themselves to be deprived of them; for this the apostle lays a special stress upon, that after they had known God, or rather were known of him, they desired to be in bondage under the weak and beggarly elements of the law.
IV. Hereupon he expresses his fears concerning them, lest he had bestowed on them labour in vain. He had been at a great deal of pains about them, in preaching the gospel to them, and endeavouring to confirm them in the faith and liberty of it; but now they were giving up these, and thereby rendering his labour among them fruitless and ineffectual, and with the thoughts of this he could not but be deeply affected. Note, 1. A great deal of the labour of faithful ministers is labour in vain; and, when it is so, it cannot but be a great grief to those who desire the salvation of souls. Note, 2. The labour of ministers is in vain upon those who begin in the Spirit and end in the flesh, who, though they seem to set out well, yet afterwards turn aside from the way of the gospel. Note, 3. Those will have a great deal to answer for upon whom the faithful ministers of Jesus Christ bestow labour in vain.