Didache 8
But let not your fasts be with the hypocrites; Matthew 6:16 for they fast on the second and fifth day of the week; but fast on the fourth day and the Preparation (Friday). Neither pray as the hypocrites; but as the Lord commanded in His Gospel, thus pray: Our Father who art in heaven, hallowed be Your name. Your kingdom come. Your will be done, as in heaven, so on earth. Give us today our daily (needful) bread, and forgive us our debt as we also forgive our debtors.
And bring us not into temptation, but deliver us from the evil one (or, evil); for Yours is the power and the glory forever. Thrice in the day thus pray.
Greek
Αἱ δὲ νηστεῖαι ὑμῶν μὴ ἔστωσαν μετὰ τῶν ὑποκριτῶν. νηστεύουσι γὰρ δευτέρᾳ σαββάτων καὶ πέμπτῃ: ὑμεῖς δὲ νηστεύσατε τετράδα καὶ παρασκευήν. μηδὲ προσεύχεσθε ὡς οἱ ὑποκριταί, ἀλλ’ ὡς ἐκέλευσεν ὁ κύριος ἐν τῷ εὐαγγελίῳ αὐτοῦ, οὕτω προσεύχεσθε: Πάτερ ἡμῶν ὁ ἐν τῷ οὐρανῷ, ἁγιασθήτω τὸ ὄνομά σου, ἐλθέτω ἡ βασιλεία σου, γενηθήτω τὸ θέλημά σου ὡς ἐν οὐρανῷ καὶ ἐπὶ γῆς: τὸν ἄρτον ἡμῶν τὸν ἐπιούσιον δὸς ἡμῖν σήμερον, καὶ ἄφες ἡμῖν τὴν ὀφειλὴν ἡμῶν, ὡς καὶ ἡμεῖς ἀφίεμεν τοῖς ὀφειλέταις ἡμῶν, καὶ μὴ εἰσενέγκῃς ἡμᾶς εἰς πειρασμόν, ἀλλὰ ῥῦσαι ἡμᾶς ἀπὸ τοῦ πονηροῦ: ὅτι σοῦ ἐστιν ἡ δύναμις καὶ ἡ δόξα εἰς τοὺς αἰῶνας. τρὶς τῆς ἡμέρας οὕτω προσεύχεσθε.