For Moses said, ‘Honor your father and your mother’; and, ‘Whoever reviles father or mother must surely die.’
Mark 7:10 ESV

Yeshua uses “Moses” as shorthand for the Torah. These aren’t the words of Moses at all (see v13), but Yeshua still uses the common vernacular in describing the words of God as the words of Moses.

There is no justification for dismissing the Law of Moses based on New Testament texts that describe it as the law or word “of Moses”, because Yeshua himself says that the written word of Moses is the word of God.