Two views of what binding and loosing with the keys of the kingdom entails:
Just as in the offering of the peace of God and the shaking off of the dust from the feet (Matthew 10:11–15), as well as in the forgiveness or judgment of sins (John 20:23), binding and loosing is the judicial authority to acquit someone or to declare someone guilty. In Semitic speech patterns, this contrast is a unit, signifying authority to proclaim salvation and redemption and to announce judgment. Peter first exerts this authority (though not exclusively, see Matthew 18:18), when, at Pentecost (Acts 2:1–47), he opens the kingdom of God for the Jews, and in the house of Cornelius (Acts 16:1–40), also for the Gentiles. The heavenly authority of the keys is now seen on earth in a provisional form, which the disciples (including all believers) together with Jesus will also fulfill when the kingdom dawns in glory (Matthew 19:28; Revelation 20:4).
One could state the function of the keys as follows: Peter must exclude from the kingdom all who do what is forbidden, and he can and must admit them again when they adhere to what is not forbidden. In other words, the command of God is the standard in the exercise of discipline, reminding us of Matthew 7:13–14.
The words
bind
andloose
in Matthew 16:19, in the context of rabbinical usage—that a person can declare something binding or not binding—mean a doctrinal authority to tell people what they can and cannot believe or do. The power to make such statements, based on the law and the prophets, belonged to the scribes. Jesus transfers that power to the disciples (see Matthew 15:14; Matthew 16:5–12).
Interpretation 1:
Binding or loosing speaks, just as in the offering of the peace of God and the shaking off of the dust from the feet (Matthew 10:11–15), as well as in the forgiveness or judgment of sins (John 20:23), of the judicial authority to acquit someone or to declare someone guilty. In Semitic speech patterns this contrast expresses a totality, and concerns the authority to proclaim salvation and redemption and to announce judgment. The fact that Peter would possess this authority first (though not exclusively, see Matthew 18:18), we see when, on the day of Pentecost (Acts 2:1–47), he opens the kingdom of God for the Jews, and in the house of Cornelius (Acts 16:1–40), also for the Gentiles. The heavenly authority of the keys is already being realized on earth, in the current, provisional form of the kingdom of heaven, which the disciples (including all believers) will also fulfill when the kingdom in glory dawns together with the Lord Jesus (Matthew 19:28, Revelation 20:4).1
One could then explain the function of the keys as follows: Peter must exclude from the kingdom those who do what is forbidden, and he can and must admit them again when they adhere to what is not forbidden. In other words, the command of God will be the standard in the exercise of discipline. One is involuntarily reminded here of Matthew 7:13–142.
Interpretation 2:
We must understand the words bind
and loose
in Matthew 16:19 against the background of its Jewish, rabbinical usage. They signify that a person can declare something binding or not binding. As such, the reference is to a doctrinal authority, by which people are informed what they can and cannot believe or do. The power to make such statements, based on the law and the prophets, belonged to the scribes. Jesus now transfers that power to the disciples (see Matthew 15:14 and Matthew 16:5–12).3
19 Je te donnerai les clés du royaume des cieux: ce que tu lieras sur la terre sera lié dans les cieux, et ce que tu délieras sur la terre sera délié dans les cieux.