If you emply modern variations, these are due to the constant endeavour of the Church to adapt herself to the contemporary man. At times there is a lack of coordination between the different countries which speak the same language, for example Britain, the U.S.A., Canada, Australia, South Africa, for English; Spain and Latin America for Spanish, Portugal and Brazil for Portuguese. But, a worldwide effort has been made, since the late sixties, in the last century, in the "Ecumenical Bibles' where most denominations take part and reach one unified text. Now, if the question refers to the two versions of the "Our Father" in the Gospels of St. Mathew (6:9-12) and Luke (11: 2-4), then one can notice the following:
(a) Both text are substantially the same and express roughly and basically same ideas.
(b) The present Matthew's "Lord's prayer" reports, in koine (colonial) Greek the Words of the Lord in a way which is very close and nearly literally translates the Hebrew and Aramaic expressions of the original pronounced by Jesus. Most of the invocations are literal quotations, done by the Lord himself and collected by him. Hebrews and Aramaic Jewish prayers but the genius of Jesus was to put them together and to give a deeply different meaning to some expressions. For instance "the Kingdom " of God was commonly thought of, in the Jewish milieu, as a world empire thanks to political and military power.
(c) Luke's Gospel, the best Greek writer in the New Testament, reproduces exactly the same words and ideasof the Lord's prayer, putting some expressions in the Greek (Hellenistic) framework - the only means to have people coming from a pagan background understand the text, memorize it and use it for the Christian Prayer "par excellence". The Jewish typical Hebrew expression "Avinu shebashamym" "Our Father in Heaven" was qouted by Jesus. It was well known in the Jewish synagogue devotion. Unfortunately, for the Jews, God was /is considered as their exclusive Father, being the "Lord and Master" of the nations. When Jesus asked us, even from pagan origin, to say "Our Father", he extended the dimensions of the "OUR" to the whole humankind. This is exactly what St. Luke reports in the universal unlimited invocation "Father", "Abba (Greek: Pater); Father of all ! In Luke 11:4 St. Luke explicates (explains) the meaning of the Aramaic "hawbaya" (debts), that it means "sins transgressions".
