Shalom.
Today is Sheni, 10-28. It is Yom, Day.
No one should fall from grace, including Christians. But to call Matthew through Revelation the New Testament and insist one only read or stay in the New Testament keeps them from the Scriptures that Paul wrote or said are inspired by God and profitable for teaching, for rebuke, for correction, and for training in righteousness, that the man of God would be adequate, equipped for every good work.
2 Timothy 3:16-17 NKJV 16 All Scripture [is] given by inspiration of God, and [is] profitable for doctrine, for reproof, for correction, for instruction in righteousness, 17 that the man of God may be complete, thoroughly equipped for every good work.
It is my belief that this is talking about the TaNaK (the Hebrew or Jewish Scriptures), not the Christian Old Testament.
Shalom.
Jacob