The keys of the kingdom - By the kingdom of heaven, we may consider the true Church, that house of God, to be meant; and by the keys, the power of admitting into that house, or of preventing any improper person from coming in. In other words, the doctrine of salvation, and the full declaration of the way in which God will save sinners; and who they are that shall be finally excluded from heaven; and on what account. When the Jews made a man a doctor of the law, they put into his hand the key of the closet in the temple where the sacred books were kept, and also tablets to write upon; signifying, by this, that they gave him authority to teach, and to explain the Scriptures to the people. - Martin. This prophetic declaration of our Lord was literally fulfilled to Peter, as he was made the first instrument of opening, i.e. preaching the doctrines of the kingdom of heaven to the Jews, Acts 2:41 ; and to the Gentiles, Acts 10:44-47 ; Acts 11:1 ; Acts 15:7 .
Whatsoever thou shalt bind on earth - This mode of expression was frequent among the Jews: they considered that every thing that was done upon earth, according to the order of God, was at the same time done in heaven: hence they were accustomed to say, that when the priest, on the day of atonement, offered the two goats upon earth, the same were offered in heaven. As one goat therefore is permitted to escape on earth, one is permitted to escape in heaven; and when the priests cast the lots on earth, the priest also casts the lots in heaven. See Sohar. Leviticus fol. 26; and see Lightfoot and Schoettgen. These words will receive considerable light from Leviticus 13:3 , Leviticus 13:23 ; : The priest shall look upon him (the leper) and pronounce him unclean. Hebrew אתו וטמא vetime otho , he shall pollute him, i.e. shall declare him polluted, from the evidences mentioned before. And in Leviticus 13:23 ; : The priest shall pronounce him clean, הכה וטהרו vetiharo hacohen , the priest shall cleanse him, i.e. declare he is clean, from the evidences mentioned in the verse. In the one case the priest declared the person infected with the leprosy, and unfit for civil society; and, in the other, that the suspected person was clean, and might safely associate with his fellows in civil or religious assemblies. The disciples of our Lord, from having the keys, i.e. the true knowledge of the doctrine of the kingdom of heaven, should be able at all times to distinguish between the clean and the unclean, and pronounce infallible judgment; and this binding and loosing, or pronouncing fit or unfit for fellowship with the members of Christ, being always according to the doctrine of the Gospel of God, should be considered as proceeding immediately from heaven, and consequently as Divinely ratified.
That binding and loosing were terms in frequent use among the Jews, and that they meant bidding and forbidding, granting and refusing, declaring lawful or unlawful, etc., Dr. Lightfoot, after having given numerous instances, thus concludes: -
"To these may be added, if need were, the frequent (shall I say?) or infinite use of the phrases, ומותר אסור bound and loosed, which we meet with thousands of times over. But from these allegations the reader sees, abundantly enough, both the frequency and the common use of this phrase, and the sense of it also; namely, first, that it is used in doctrine, and in judgments, concerning things allowed or not allowed in the law. Secondly, that to bind is the same with, to forbid, or to declare forbidden. To think that Christ, when he used the common phrase, was not understood by his hearers in the common and vulgar sense, shall I call it a matter of laughter, or of madness?
To this, therefore, do these words amount: When the time was come wherein the Mosaic law, as to some part of it, was to be abolished, and left off, and, as to another part of it, was to be continued and to last for ever, he granted Peter here, and to the rest of the apostles, Matthew 18:18 , a power to abolish or confirm what they thought good, and as they thought good; being taught this, and led by the Holy Spirit: as if he should say, Whatsoever ye shall bind in the law of Moses, that is, forbid, it shall be forbidden, the Divine authority confirming it; and whatsoever ye shall loose, that is, permit, or shall teach that it is permitted and lawful, shall be lawful and permitted. Hence they bound, that is forbade, circumcision to the believers; eating of things offered to idols, of things strangled, and of blood, for a time, to the Gentiles; and that which they bound on earth was confirmed in heaven. They loosed, that is, allowed purification to Paul, and to four other brethren, for the shunning of scandal; Acts 21:24 ; and, in a word, by these words of Christ it was committed to them, the Holy Spirit directing, that they should make decrees concerning religion, as to the use or rejection of Mosaic rites and judgments, and that either for a time, or for ever.
"Let the words be applied by way of paraphrase to the matter that was transacted at present with Peter: 'I am about to build a Gentile Church,' saith Christ, and to thee, O Peter, do I give the keys of the kingdom of heaven, that thou mayest first open the door of faith to them; but if thou askest by what rule that Church is to be governed, when the Mosaic rule may seem so improper for it, thou shalt be so guided by the Holy Spirit, that whatsoever of the law of Moses thou shalt forbid them shall be forbidden; whatsoever thou grantest them shall be granted; and that under a sanction made in heaven.' Hence, in that instant, when he should use his keys, that is, when he was now ready to open the gate of the Gospel to the Gentiles, Acts 10, he was taught from heaven that the consorting of the Jew with the Gentile, which before had been bound, was now loosed; and the eating of any creature convenient for food was now loosed, which before had been bound; and he in like manner looses both these.
"Those words of our Savior, John 20:23 , Whose sins ye remit, they are remitted to them, for the most part are forced to the same sense with these before us, when they carry quite another sense. Here the business is of doctrine only, not of persons; there of persons, not of doctrine. Here of things lawful or unlawful in religion, to be determined by the apostles; there of persons obstinate or not obstinate, to be punished by them, or not to be punished.
"As to doctrine, the apostles were doubly instructed. 1. So long sitting at the feet of their Master, they had imbibed the evangelical doctrine.
"2. The Holy Spirit directing them, they were to determine concerning the legal doctrine and practice, being completely instructed and enabled in both by the Holy Spirit descending upon them. As to the persons, they were endowed with a peculiar gift, so that, the same Spirit directing them, if they would retain and punish the sins of any, a power was delivered into their hands of delivering to Satan, of punishing with diseases, plagues, yea, death itself, which Peter did to Ananias and Sapphira; Paul to Elymas, Hymeneus, and Philetus, etc."
After all these evidences and proofs of the proper use of these terms, to attempt to press the word, into the service long assigned them by the Church of Rome, would, to use the words of Dr. Lightfoot, be "a matter of laughter or of madness." No Church can use them in the sense thus imposed upon them, which was done merely to serve secular ends; and least of all can that very Church that thus abuses them.