You are wrong as it would be the Greek proposition [FONT=Theophilos Greek, sans-serif]εν[/FONT] but it is instead[FONT=Theophilos Greek, sans-serif] εις[/FONT]
i'd repent of false teaching if i were you.
Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit,
The propagation of the gospel is a work for all in their several spheres. Teach; docete (Vulgate). These are unfortunate renderings of the verb μαθητεύσατε, which means, "make disciples." Teaching is expressed in ver. 20, as one of the elements or components of full discipleship. The imperative aorist μαθητεύσατε is, as it were, decomposed by the two following present participles, "baptizing" and "teaching." In the case of infants the process is exactly what is here represented; they are admitted into the Christian society by baptism, and then instructed in faith and duty.
Adults have to be instructed before baptism; but they form a small minority in most Christian communities, where, generally, infant baptism is the rule, and would be regarded rather as exceptions. Teaching alone is not stated by the Lord to be the only thing necessary to convert an unbeliever into a Christian; this is effected by the grace of God applied as Christ proceeds to explain. All nations (πάντα τὰ ἔθνη αλλ τηε νατιονσ).
The apostles were no longer to go only to "the lost sheep of the house of Israel" (Matthew 10:6); they were to Christianize all the nations of the world, Jew and Gentile alike. The gospel is adapted to all the varying minds and habits of men, barbarous and civilized, near and remote, ignorant or cultivated; and it is the duty and privilege of Christ's ministers to make it known and acceptable in all quarters of the globe. Baptizing them; i.e. individuals of all the nations.
The present participle denotes the mode of initiation into discipleship. Make them disciples by baptizing them. Christ thus explains his mysterious announcement to Nicodemus (John 3:5), "Except a man be born of water and the Spirit, he cannot enter into the kingdom of God." To the disciples the notion of baptism was no new thing. As a rite typifying the cleansing of the heart and the purpose of leading a new life, it had been long practised in the case of proselytes to the Jewish faith; they had seen it employed by John the Baptist (Matthew 3:6), and had used it themselves (John 4:1, 2).
Christ adopts the old rite, gives it a new solemnity, a most sacred formula of administration, a new meaning, new spiritual effects. The persons to whom and in whose presence he spoke would understand his injunction as applicable to all who were capable of its reception, children and adults, the subjects of the initiatory ceremony of proselytism.
There was no need of closer specification. Or, if any such instruction was needed, the rules concerning circumcision would be a sufficient guide. In (εἰς, into) the Name of the Father, and of the Son, and of the Holy Ghost. Our version follows the Vulgate, in nomine, which does not give the right force to the expression. The phrase does not mean merely invoking the Name, under the sanction of the great Name, but something more than this.
It signifies into the power and influence of the Holy Trinity, into faith in the three Persons of God, and the duties and privileges consequent on that faith, into the family of God and obedience unto its Head. The "into" shows the end and aim of the consecration of baptism. The "Name" of God is that by which he is known to us - that which connotes his being and his attributes, that by which there exists a conscious connection between God and ourselves (comp. Matthew 18:20).
So being baptized into the Name of God implies being placed in subjection to and communion with God himself, admitted into covenant with him. It is to be observed that the term is "name," not "names," thus denoting the unity of the Godhead in the trinity of Persons. The Lord's words have always been taken as the formula of baptism, and have in all ages been used in its administration.
The three Divine Persons were revealed at the baptism of Jesus (Matthew 3:16, 17); they are invoked at every Christian baptism. It is true that we read, in the early Church, of persons being baptized "in the Name of the Lord Jesus," and "in the Name of the Lord" (Acts 8:16; Acts 10:48); but this expression by no means assumes that the names of the other Divine Persons were not used; it denotes that the converts were admitted into the religion which Jesus instituted, in fact, were made Christians....
Matthew Henry