"That's Old Testament stuff." Ever heard that? Are Matthew, Mark, Luke, and John really "New Testament?" Think about it. Testament, will (as in, 'last will and testament'), and covenant are often used, yet Jesus identified more sections: "My words" (the New Testament), the law of Moses, the prophets, and the psalms." (Lk 24:44)
Of these four sections, only the law of Moses (about Ex. 12 through Deut.) is the old covenant. Would this impact your understanding of God's laws?
[Now He said to them, “These are My words which I spoke to you while I was still with you, that all things which are written about Me in the Law of Moses and the Prophets and the Psalms must be fulfilled.”]