Not so, Lord. This is the voice of him which doth as well refuse, as also object to God his own commandment; for he is afraid, for good causes, to touch that which he knew was forbidden him in the law of God, (Leviticus 11:21, etc.) Therefore he objecteth to God the law which he himself made, lest he should break the same unadvisedly. There was a certain show of repugnancy between the law and the vision; therefore Peter is not hasty, but desireth first to have his doubt dissolved before he depart from observing the law. Yet it is a strange matter why Peter resisted more in meats than did Abraham in killing his son; for Abraham [might have] had more things to object, (Genesis 22:9, 10.) I dare not here say that that befell Peter which is too common among men, to stand more about outward and small matters than about the chief points of the law; I rather make that answer which is out of doubt, that Abraham's mind was so persuaded, and that he was furnished with such power of the Spirit, that he overcame with 1ofty and heroical fortitude all those things which might have hindered him. But the Spirit of God wrought slenderly, [1] in Peter; whereby we are taught that every small or light thing doth cause us to doubt, unless the Lord do furnish us with counsel and constancy to overcome all fear. Yet Peter dealeth very godly and very religiously, in that being in doubt amidst divers cogitations, he dare do nothing until it better appear what he ought to follow. Common signifieth in this place profane. For because the Lord (as we have said) had chosen the Jews to be a peculiar people, he had prescribed unto them this rite and manner of living, that it might distinguish them from the profane Gentiles. Therefore, whatsoever the Gentiles did use contrary to the rule of the law, that did they call common, because there was nothing pure or holy but that which God had appointed for the use of his people.

Footnotes

1 - "Lente," slowly.

I have never eaten - In the Old Testament God had made a distinction between clean and unclean animals. See Leviticus. 11:2-27; Deut. 14:3-20. This law remained in the Scriptures, and Peter pled that he had never violated it, implying that he could not now violate it, as it was a law of God, and that, as it was unrepealed, he did not dare to act in a different manner from what it required. Between that law and the command which he now received in the vision there was an apparent variation, and Peter naturally referred to the well known and admitted written Law. One design of the vision was to show him that that Law was now to pass away.
That is common - This word properly denotes "what pertains to all," but among the Jews, who were bound by special laws, and who were prohibited from many things that were freely indulged in by other nations, the word "common" came to be opposed to the word "sacred," and to denote what was in common use among the pagans, hence, that which was "profane," or "polluted." Here it means the same as "profane," or "forbidden."
Unclean - Ceremonially unclean; that is, what is forbidden by the ceremonial law of Moses.

Common or unclean - By common, κοινον, whatever was in general use among the Gentiles is to be understood; by ακαθαρτον, unclean, every thing that was forbidden by the Mosaic law. However, the one word may be considered as explanatory of the other. The rabbins themselves, and many of the primitive fathers, believed that by the unclean animals forbidden by the law the Gentiles were meant.

(2) But Peter said, Not so, Lord; for I have never eaten any thing that is common or unclean.
(2) Peter learns daily in the knowledge of the benefit of Christ, yea, even after he had received the Holy Spirit.

But Peter said, not so, Lord,.... God forbid I should do this, so contrary to the law of God, and to my own practice, throughout the whole course of my life:
for I have never eaten anything that is common or unclean; in a ceremonial sense, which was in common use with Gentiles, but unclean by the law of Moses: this shows that Peter as yet closely adhered to the ceremonial law, nor did he know that it was abolished by Christ; and notwithstanding the commission given to him and the rest of the apostles to preach the Gospel to every creature, and the extraordinary gifts of speaking with divers tongues for that purpose, bestowed on them at the day of Pentecost; yet he and they remained greatly strangers to the calling of the Gentiles, and the admitting of them to a civil and religious conversation with them; the knowledge of every truth was not at once communicated to them, but gradually, as it pressed the Lord to enlighten their minds.

Not so, Lord--See Marginal reference.
I have never eaten anything that is common--that is, not sanctified by divine permission to eat of it, and so "unclean." "The distinction of meats was a sacrament of national distinction, separation, and consecration" [WEBSTER and WILKINSON].

But Peter said, In nowise, Lord - When God commands a strange or seemingly improper thing, the first objection frequently finds pardon. But it ought not to be repeated. This doubt and delay of St. Peter had several good effects. Hereby the will of God in this important point was made more evident and incontestable. And Peter also, having been so slow of belief himself, could the more easily bear the doubting of his brethren, Acts 11:2, &c.