Canon 98
About the prohibition to marry “another betrothed during the lifetime of her betrothed.”
Anyone who enters into a marriage relationship with a woman who is betrothed to another, while the betrothed is still alive, must be charged with adultery.
Greek original
Ὁ ἑτέρῳ μνηστευθεῖσαν γυναῖκα, ἔτι τοῦ μνηστευσαμένου ζῶντος, πρὸς γάμου κοινωνίαν ἀγόμενος, τῷ τῆς μοιχείας ὑποκείσθω ἐγκλήματι.
Parallel canons
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