signs of the times. See note on Matthew 12:39.

wicked and adulterous generation. The same words of rebuke had been spoken to another group of scribes and Pharisees as Jesus now spoke to, presumably, a different group of Pharisees and Sadducees (see Matthew 12:39). They should have been able indeed to discern the many “signs of the times” of Messiah's first coming that were evident all around them. Just so, people today can see the numerous signs of His imminent second coming in the form of fulfilled prophecies. There is no need for special “signs and wonders,” such as many are seeking.

beware of the leaven. The dangerous doctrine of the Pharisees was legalism and of the Sadducees skepticism, both of which types of doctrinal leaven are very much in evidence in the religious world today.

doctrine. As indicated before, leaven is a substance which instigates a decay process and thus symbolizes false doctrine. See notes on Matthew 13:32-33.

Thou art the Christ. Peter's great confession apparently was given as spokesman for all the disciples since Jesus had asked them the question (Matthew 16:15). They understood that Jesus was both the promised Messiah (i.e., “the Christ”) and also the only begotten Son of God. They had learned this first of all from John the Baptist (see John's testimony as recorded in John 1:15-18), but this had been further confirmed by their personal knowledge of Christ and by the inward witness of the Holy Spirit.

Peter. The Lord is here making a play on words; in the Greek, “Peter” is petros, meaning a small stone, whereas “rock” is petra, meaning a great rock mass, solid and immovable. Even if Jesus was speaking in Aramaic, in which both meanings are expressed simply by Cephas, He was making a distinction between the two (perhaps by gestures) which Matthew picked up and (under divine inspiration) translated by the two different Greek words.

The massive rock foundation on which Christ would build His Church was Peter's great confession of Jesus as the Creator and the Son of the living God. Peter (representing the twelve and, indeed, all who would make the same confession) would be living stones in the church built on the foundation of such confession (1 Peter 2:5; Ephesians 2:19-22).

my church. This is the first, and definitive, use of the word “church” (Greek ekklesia, or “out-called assembly”) in the New Testament. This church built by Christ clearly consists of all who acquiesce volitionally and spiritually in Peter's great confession. This in neither an invisible church, for it is composed of real people, nor a universal church, relative to the world as a whole, but always only a “little flock” (Luke 12:32). The church can never assemble together as a whole until it gathers in heaven as “the general assembly and church of the firstborn” (Hebrews 12:23). It is represented, however, as a “local assembly” in each time and place where “two or three are gathered together in my name” (Matthew 18:20), for Christ Himself, by the Holy Spirit, is there “in the midst of them.” Normally such gatherings would be formally structured as local churches (of the 115 occurrences of ekklesia, at least 85 refer specifically to local churches), with members, officers and organized programs of winning, baptizing and teaching converts.

gates of hell. “Hell” here is the Greek hades, not the ultimate lake of fire but the present pit in the heart of the earth where the souls of the lost, as well as a host of fallen angels, are confined awaiting judgment. When Christ spoke these words, the souls of believers were also there, but during His three days in the grave, Christ stormed the gates of Hades and set these redeemed captives free, taking them with Him to paradise (Ephesians 4:8-10). In like manner, He assures those in His Church that they also can deliver lost souls from imminent confinement behind the gates of Hades as they proclaim the great confession of Christ as redeeming Son of God to all who will heed the gospel.

keys of the kingdom. The “keys” here are not literal keys, of course, but rather a metaphor for the message that would open the way to salvation for those hearers who would respond. A similar figurative use of a “key” is in Luke 11:52, where Jesus charged the lawyers of His day with taking away “the key of knowledge.” Peter, representing all the apostles, used these keys (i.e., the gospel message) to open the door to the Jews at Pentecost, then to the believers of Samaria, then to the Gentiles at the house of Cornelius (Acts 2:14-41; 8:14-17; 10:17-48).

shall be bound. The phrases “shall be bound” and “shall be loosed” can better be translated “shall have been bound” and “shall have been loosed.” Not only Peter but all the apostles (note John 20:21-23) would have the authority to pronounce to their listeners the binding or loosing that would have been established in heaven as an immediate result of the response of these listeners to the gospel message. Note also Matthew 18:18.

tell no man. The gospel records give no indication that the disciples ever acknowledged that Jesus was the Christ prior to this confession of Peter's, although they almost certainly realized it. By this stage of His public ministry, He evidently planned to concentrate on teaching and training His disciples for their own future ministry.

From that time forth. Once the disciples had formally recognized Him as the Messiah, the Lord began to prepare them for His real mission—and theirs. Remarkably, He even prophesied His own resurrection! In spite of this, however, His death and resurrection caught them by surprise. Somehow they still felt He would lead them in establishing the Messianic kingdom without this very uncomfortable interruption.

rebuke him. It is surprising that Peter could make such a remarkable (even Spirit-inspired) confession of Jesus as both Messiah and Son of God, then almost immediately deny Christ's Word! Jesus recognized that this was really Satan speaking through Peter (Matthew 16:23)—not in the sense of Satanic possession, but rather Satanic persuasion. The natural man almost instinctively recoils against the idea of the atoning death and resurrection of Christ, and Satan bitterly resists it.

gain the whole world. This is a remarkable profit-and-loss statement! The Greek word for “soul” is psuche, from which we have our English word “psychology,” meaning “study of the soul.” Although it can also mean “life,” depending on context, the emphasis and comparison here seems clearly to refer to one's eternal soul. It is ironic today that the “science” of psychology, for the most part, is so committed to evolutionism that its leaders deny the very existence of an eternal soul.

not taste of death. The disciples were to see Him “coming,” not actually reigning, in His kingdom. This clearly referred to the remarkable vision which three of His disciples were about to see on the Mount of Transfiguration.

coming in his kingdom. Peter confirms that they saw the “coming” of our Lord Jesus Christ, and were “eyewitnesses of His majesty … when we were with Him in the holy mount” (2 Peter 1:16-18).