opusdei 1972
For instance, Papias said that Matthew wrote in Hebrew language a collection of sayings. This seemed to be the Gospel used by Nazarenes and Hebionites, who were christians that rejected the divinity of Jesus, regarding him only as the Messiah. Nevertheless, Jerome, an "orthodox" church father at the end of the fourth century wrote that most christians believed that that Gospel used by these sects was the original one written by Matthew. And if you read Jerome's and Eusebius' quotations from that Gospel you will notice that many statements differ from that of the greek version of Matthew's Gospel. So it means that many christians of the fourth century were not convinced of the authenticity of greek version of the Matthew's Gospel that we currently have.
I thought that this is already an accepted fact anyway, namely that Matthew was written originally in aramaic or hebrew.
Theologian Pope Benedict mentioned for instance Papia's testimony for Matthew on 30th Aug, 2006
"Finally, it should be recalled that the tradition of the early church unanimously Matthew ascribes authorship of the first Gospel. This is already happening by Papias, who was Bishop of Hierapolis in Phrygia about the year 130. He writes: "Matthew has compiled the speeches in Hebrew; everyone interpreted them as best he could "(in Eusebius of Caesarea, Ecclesiastical History, III, 39). The historian Eusebius adds: "Matthew, who had first preached among the Hebrews, wrote when he wanted to go also to the other nations his gospel in his native language; because he sought whom he left to replace by Scripture what they lost with his departure "(ibid., III, 24).
We have the Gospel written by Matthew in Hebrew or Aramaic no longer, but in the Greek Gospel that we have, we as it were listening the compelling voice of the Matthew who, became the apostle so continues this saving mercy of God to proclaim. Let us listen to this message of St.. Matthew, we always think back about it, so that we learn to stand up and follow Jesus with determination.
[the text is on basis of goole translation and not edited perfectly]
Whether later redaction in greek or second took place, a second, third redaction, hat changed matthews theology and doesnt fit into his concepts and whether new concepts were later added are interesting field of research.