Wiki:
Binding and loosing is an originally
Jewish phrase which appears in the
New Testament, as well as in the
Targum. In usage
to bind and
to loose mean simply
to forbid by an indisputable authority, and
to permit by an indisputable authority. The Targum to a particular
Psalm implies that these actions were considered to be as effectual as the spell of an
enchanter.
The
poseks had, by virtue of their ordination, the power of deciding disputes relating to
Jewish religious law. Hence the difference between the two main schools of thought in early classical Judaism were summed up by the phrase
the school of Shammai binds; the school of Hillel looses.
Theoretically, however, the authority of the poseks proceeded from the
Sanhedrin, and there is therefore a
Talmudic statement that there were three decisions made by the
lower house of judgment (the Sanhedrin) to which the
upper house of judgment (the heavenly one) gave its
supreme sanction. The claim that
whatsoever [a disciple] bind or loose on earth shall be bound or loosed in heaven, which the Gospel of Matthew attributes to Jesus, is probably therefore just an adoption of a phrase popular at the time.
