Matthew 18:20

20Whereοὗforγάρareεἰσινtwoδύοorἢthreeτρεῖςgathered togetherσυνηγμένοιuntoεἰςτὸMyἐμὸνnameὄνομα,thereἐκεῖam Iεἰμιinἐν[the] midstμέσῳof themαὐτῶν.

For where two or three are gathered together unto My name, there am I in their midst.”