Flavius Josephus, a Jewish historian during the first century AD discussed the Hebrew Scriptures in the time of Jesus in an apologetic work written against a non-Jew named Apion. Josephus writes about the superiority of the Hebrew Scriptures over pagan writings in his work, Against Apion (1.8).
For example, Josephus argues in this defense of the Jewish Scriptures that the Jews have a relatively small number of sacred books containing the Law, the Prophets, and the Wisdom Writings, instead of a multitude of books like the pagans. Although the Jews arranged and labeled the Old Testament books differently than what we as Christians call them, Josephus clearly presented a list of books in the Hebrew Bible that resembles the books we have in the Old Testament of our Christian Bible.
The Hebrew Scripture originated as early as the time of Moses. Exodus 24 describes how Moses wrote down God’s words for the Israelites. We can read how this first happened:
Then he [God] said to Moses, “Come up to the Lord, you and Aaron, Nadab and Abihu, and seventy of the elders of Israel. You are to worship at a distance, but Moses alone is to approach the Lord; the others must not come near. And the people may not come up with him.” When Moses went and told the people all the Lord’s words and laws they responded with one voice, “Everything the Lord has said we will do.” Moses then wrote down every thing the Lord had said. (Exodus 24:1-4)
In this way, Moses provided the Israelites with a written record of God’s mighty deeds and words (Exodus 34:1, 27).
These laws were given as a gift after the Hebrews experienced redemption from slavery–not as a means to achieve redemption from slavery. God’s commands were a gift, among other things, to protect God’s people from the perils of assimilating to the threats from the surrounding cultures.
Then, at the end of his life, Moses took all that God had revealed to him and gave it to the priests of Israel:
So Moses wrote down this law and gave it to the priests, the sons of Levi who carried the ark of the covenant of the Lord, and to all the elders of Israel. Then Moses commanded them: “At the end of every seven years, in the year for canceling debts, during the feast of Tabernacles, when all Israel comes to appear before the Lord your God at the place he will choose, you shall read this law before them in their hearing. Assemble the people–men, women and children, and the aliens living in your towns–so they can listen and learn to fear the Lord your God and follow carefully all the words of this law (Deuteronomy 31:9-12).
God commanded that every seven years the law was to be read aloud to the whole community. God also commanded the parents to teach these laws to their children on a daily basis in a well-known passage called the Shema (which means “to hear, listen, or obey” in Hebrew):
Hear, O Israel: The Lord our God, the Lord is one. Love the Lord your God with all your heart and with all your soul and with all your strength. These commandments that I give you today are to be on your hearts. Impress them on your children. Talk about them when you sit at home and when you walk along the road, when you lie down and when you get up. Tie them as symbols on your hands and bind them on your foreheads. Write them on the doorframes of your houses and on your gates (Deuteronomy 6:4-9).
Our longest song/hymn in the Psalter of Israel (Psalm 119) is an acrostic song (easier to memorize and teach) about the joy and delight of keeping/walking with God’s law.
So from the very beginning, the Old Testament writings presented themselves as the inspired message of God to his people.
God loved his people enough to know that they needed an objective and authoritative standard to guide them in their relationship with him. That’s why he gave the commandments—so we would know how to relate to him.
Earlier in Deuteronomy, God was specific about the application of his law and the importance of not changing what had been revealed.
Hear now, O Israel, the decrees and laws I am about to teach you. Follow them so that you may live and may go in and take possession of the land that the Lord, the God of your fathers, is giving you. Do not add to what I command you and do not subtract from it, but keep the commands of the Lord your God that I give you (Deuteronomy 4:1–2).
God wanted to ensure that the Israelites understood his sacred ordinances: they were the daily standard for living and to be adhered to in all things without any changes (see also Deuteronomy 4:5-9; 5:29-33; 6:1, 4-9; 7:12; 8:1, 6; etc.).
At the same time, God’s revelation through Moses was not God’s final word.
As the Israelite nation developed, God continued to communicate with his people. Sometimes he would inspire the chronicling of important lessons in Israelite history, as he did in the books of Joshua through 2 Chronicles. At other times, God would raise up prophets like Isaiah and Jeremiah who spoke for God to the people and those words were written down. They were never merely human words. They were the very words of God.
The Israelites believed more revelations would come, so God gave them tests to determine whether a prophet was really speaking for God (Deut. 18:14-22; see also Deut. 13:1-5). God also told Moses that there would be one special prophet who would come and the people were to heed the words of this new prophet, because his words would be those of God himself.
I will raise up for them a prophet like you from among their brothers; I will put my words in his mouth, and he will tell them everything I command him. If anyone does not listen to my words that the prophet speaks in my name, I myself will call him to account (Deuteronomy 18: 18-19).
The Old Testament writings anticipated a climactic revelation from God (Jer. 31:31–34; Isa. 11:1–5). This prophet did come, and we now know him as Jesus Christ (John 1:45).
Though people and ideas would change, the Israelites had a standard to ensure that they stayed on the right track and remained faithful to God.
Jewish parents believed that God commanded them to teach the Old Testament writings to their children, so everyday children were required to learn to read and write. Josephus said that God’s law “orders that (children) shall be taught to read and shall learn both the laws and the deeds of their forefathers.”
Jewish boys generally memorized portions of the Old Testament starting at five or six years of age. Some rabbis and scribes committed the entire Old Testament to memory. Josephus stated that the Jews had such a high view of Scripture they were willing to die for it.
 The same mindset is reflected in the teachings of Jesus in the Gospels. See the definitive work on Christ’s views in the book by John Wenham, Christ and the Bible, third edition (Eugene, Oregon: Wipf & Stock Pub., 2009)
 Josephus Ag. Ap. 2.204; see Craig Evans, Jesus and the Remains of the Day (Hendrickson Publishing, 2015), 70.
 See Craig Evans, Jesus and the Remains of the Day (Hendrickson Publishing, 2015) and Ann Spangler and Lois Tverberg, Sitting at the Feet of Rabbi Jesus: How the Jewishness of Jesus Can Transform Your Faith (Grand Rapids, Michigan: Zondervan, 2009), 24.