“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.” Then He opened their minds to understand the Scriptures”
By Jesus “separating” the Psalms from “the Prophets,” He was acknowledging the THREE-fold division of the OT canon which Jesus still considered & called “Scripture,” which both Protestants recognize in their OT, as well as Jews do their TaNaKh, which would exclude the Apocrypha & the “additions” to Daniel & Esther which were not originally part of those OT books, but later “added” during the intertestimental period. This THREE-fold division described by Jesus is not the same as the FOUR-fold division in the Catholic OT, where the later Apocrypha books were “added” & “blended” into the OT:
Torah: Genesis, Exodus, Leviticus, Numbers, Deuteronomy;
Historical books: Joshua, Judges, Ruth, 1 Samuel, 2 Samuel, 1 Kings, 2 Kings, 1 Chronicles, 2 Chronicles, Ezra, Nehemiah, Tobit, Judith, Esther, 1 Maccabees, 2 Maccabees;
Sapiential (Wisdom) books: Job, Psalms, Proverbs, Ecclesiastes, Song of Solomon, Wisdom, Sirach;
Prophetic books: Isaiah, Jeremiah, Lamentations, Baruch, Ezekiel, Daniel, Hosea, Joel, Amos, Obadiah, Jonah, Micah, Nahum, Habakkuk, Zephaniah, Haggai, Zechariah, Malachi