Matthew 18:20
Since Christ gives those appointed to teach authority to loose and to bind — once people have turned toward desire for virtue and do not wander off again — one must fear the holy ones’ voices, even if those who decide are not many. Christ has also assured us of this: he did not say a decision is firm only when it comes from many, but promised that if even two should decide in concord and with care, it will come to pass. “For I will be with them,” he says, “and join in the decision, if only two are gathered because of me.” (Matthew 18:18–20) It is not the number of those present, he says, but the power of piety and love of God that will be effective.
Greek
Ἐπειδὴ δίδωσι τοῖς τὸ διδάσκειν λαχοῦσιν ἐξουσίαν τοῦ λύειν καὶ δεσμεῖν ὁ Χριστὸς μὴ 25 μεταφοιτώντων τῶν ἅπαξ ἐκκλινάντων πρὸς ἔφεσιν ἀρετῆς, χρὴ δεδιέναι τὰς τῶν ἁγίων φωνάς, κἂν μὴ πολλοί τινες εἶεν οἱ διορίζοντες· πεπληροφόρηκε γὰρ καὶ τοῦτο ἡμᾶς ὁ Χριστός, οὐχὶ δήπου πάντως ὅ τι ἐκ πολλῶν ἔσται βέβαιον εἰπών, ἀλλ' εἰ καὶ δύο τὸν ἀριθμὸν συμφώνως καὶ περιεσκεμμένως ὁρίσειαν, εἰς πέρας ἥξειν ἐπαγ γειλάμενος· συνέσομαι γάρ φησι καὶ συνοριῶ, εἰ μόνοι δύο συναχθεῖεν δι' ἐμέ· οὐ γὰρ <τὸν> τῶν συνόντων ἀριθμόν, ἀλλὰ τὴν τῆς εὐσεβείας καὶ φιλοθεΐας δύναμιν ἐνεργὸν γενήσεσθαί φησιν.