The ABC program made it clear that the Catholic doctrine of the
sacred indissolubility of marriage, which was solemnly canonized at
the Council of Trent,[10] is at stake. This doctrine is also one of
the tension points in the ecumenical dialogue between the Catholic
Church and the Eastern Orthodox Churches. The tension is present
because of divergent interpretations of the so-called exceptive
clause of Matt. 5:32 and Matt. 19:9. The roots of divergence may be
found toward the end of the eighth century when, "in order to
guarantee peace and harmony for the Church,"[11] Patriarch Tarsisius
decided in Emperor Constantine VI's "Moechian[12] Affair"[13] to
tolerate remarriage after divorce and "not to inflict severe
canonical penalties on one who has transgressed the divine
precept."[14] However, it was about three centuries later that "from
about the beginning of the second millennium (as far as one can
ascertain) the Eastern Church accepted fully that the clause in Matt.
5:32 and 19:9 referring to 'unchastity' constituted an exception to
the rule and in the case of adultery divorce and remarriage was to be
permitted."[15]

The Catholic Church makes an implicit statement of her understanding
of the exception through her tribunal system. The Eastern Orthodox
Churches implicitly point out their understanding of the exception by
applying their canonical institute of or "economy"
(administration)[16] to marriage cases. Some Catholic clergymen who
do not accept the internal forum solution, reasoning that the
Orthodox Church also is founded on the apostles, wonder why the
Catholic Church does not adopt this avenue to remarriage after
divorce.

Briefly, and without intending any offense to our Eastern separated
brothers, it must be said that difficulties exist both in the
institute itself and in its basis on the Matthean divorce pericope
without giving full force to the Lord's "solution" in Matt. 19:12b.

As a general institute, economy can be assimilated by Western legal
minds, if ever, only with the maximum of difficulty. "It seems to
belong to the science of jurisprudence; it can solve seemingly
insoluble issues.... There are many explanations of economy in
Western literature; few of them are faithful to the Eastern
original."[17]

The weakness in the institute may be seen especially in its
application to marriage cases. Even though its use is restricted to
bishops or even to a synod of bishops,[18] the Orthodox have not been
able to limit it to the case of adultery. For "the Orthodox Church,
while continuing to uphold the right of an innocent spouse to divorce
and remarriage in the case of adultery, gradually has come to grant
the same freedom to those who are victims of other types of
misbehavior by their spouses, such as cruelty, abandonment, or
serious neglect of duties toward the family."[19] Once the Orthodox
went from dissolution because of to "divorce . . .
permissible under circumstances for grave causes which make married
life impossible,"[20] they placed themselves in danger of giving
no-fault documents of freedom to remarry.