Matthew has a number of issues that calls its credibility into question. First, the literary structure is summarized in Devised Literary Structure of Matthew. The Gospel of Matthew was written after the Gospel of Mark was written. Matthew is clearly dependent on Mark for much of its content since 95% of the Gospel of Mark is found within Matthew and 53% of the text is verbatim (word-for word) from Mark. The Gospel is attributed to Matthew because of the presumption that some of the unique source material may had come from Matthew (a disciple of Jesus who was previously a tax collector) although most of the source material is from the Gospel of Mark as many see it is an embellishment upon Mark. What is clear is that Matthew is the combination of source materials rather than that of a single disciple or source.
Matthew has a number of conflations and misquotes of prophecy documented in Prophecy Conflations and Misquotes.
Embellishments of Matthew are also documented corresponding to historical claims and significant statements that are not attested anywhere else in the New Testament.
Implications of Farrer Theory addresses how the Farrer-Goulder-Goodacre hypothesis is a basis for increase skepticism toward Matthew
Corrections by Luke over Matthew documents places where Luke makes a correction or clarification to Matthew.
Contradictions of Matthew are those most blatantly obvious contradictions of Matthew with other Gospels.
Origin of Matthew addresses the context and authorship of Matthew.
Evidence that Mathew was composed for Liturgical use is provided in Matthew is a Liturgical Document.
Critical Scholarship of Matthew provides key references of critical scholarship with extensive book excerpts.
Additionally, evidence is provided against the traditional wording of Matthew 28:19 regarding the baptismal formula indicating it may have been added later