John Calvin Commentary 1 John 2:20

"And ye have an anointing from the Holy One, and ye know all the things." — 1 John 2:20 (ASV)

But you have an unction. The Apostle modestly excuses himself for having so earnestly warned them, so that they would not think that they were indirectly reproved, as though they were unrefined and ignorant of those things which they should have known well. So Paul acknowledged that the Romans possessed wisdom, being able and fit to admonish others. He at the same time showed that they needed to be reminded, in order that they might rightly perform their duty (Romans 15:14, 15). The Apostles did not, however, speak in this way to flatter them; but they wisely took care in this manner so that their doctrine would not be rejected by anyone, for they declared what was suitable and useful, not only to the ignorant, but also to those well instructed in the Lord’s school.

Experience teaches us how fastidious the ears of men are. Such fastidiousness should indeed be far away from the godly; yet it is necessary for a faithful and wise teacher to omit nothing by which he may secure a hearing from all. And it is certain that we receive what is said with less attention and respect when we think that the one who speaks disparages the knowledge that has been given to us by the Lord. The Apostle, by this praise, at the same time stimulated his readers, because those who were endowed with the gift of knowledge had less excuse if they did not surpass others in their proficiency.

The situation is that the Apostle did not teach them as though they were ignorant and acquainted only with the first elements of knowledge, but reminded them of things already known, and also exhorted them to stir up the sparks of the Spirit, so that a full brightness might shine forth in them. And in the next words he explained himself, clarifying that he did not write to them because they were ignorant of the truth, but rather because they had been well taught in it; for if they had been entirely ignorant and novices, they could not have comprehended his doctrine.

Now, when he says that they knew all things, this is not to be taken in the widest sense, but should be confined to the subject discussed here. But when he says that they had an unction from the Holy One, he alludes, no doubt, to the ancient types. The oil by which the priests were anointed was obtained from the sanctuary; and Daniel mentions the coming of Christ as the proper time for anointing the Most Holy (Daniel 9:24). For he was anointed by the Father, that he might pour forth on us a manifold abundance from his own fullness. Therefore, it follows that men are not rightly made wise by the acumen of their own minds, but by the illumination of the Spirit; and further, that we are not made partakers of the Spirit in any other way than through Christ, who is the true sanctuary and our only high priest.