Shalom,
Often Christians think that the "Old Testament" is virtually irrelevant today, since the doctrines of the Church are made explicit in the New Testament writings. However, this is a serious mistake, as the following facts will demonstrate:
1.
Yeshua (Jesus) and all his disciples were Torah-observant Jews. The Scriptures which they studied, loved, and quoted were the Torah, the Prophets, and the Writings (the Jewish Tanakh). Indeed, Yeshua quoted from the book of Deuteronomy (from the Torah) more than any other book in the Scriptures. As a child, Yeshua would have studied the Torah and memorized it with other Jewish children. He would also have been familiar with the teaching of the earlier Jewish sages of Israel.
When asked what was the greatest commandment of the LORD, Yeshua quoted the ve'ahavta portion of the Shema : ve'ahavta et Adonai eloheykha be'khol-levavkha, u'vekhol nafshekha, u'vekhol me'odekha,
"And you shall love the LORD your God with all your heart, with all your soul, and with all your strength" (Deu 6:5), and then He added the commandment, v'ahavta l're'akha kamokha - ani Adonai , "You shall love your neighbor as yourself" (Lev 19:18). Both of these commandments come directly from the Torah.
Indeed, Yeshua said that He did not come to abolish the Torah or the Prophets, but to fulfill them (Mat 5:17-19). He later told a prospective follower of His, "If you would enter life, keep the commandments" (Mat 19:17). When He was further asked which ones, Yeshua replied by citing the Ten Commandments and appealed to the man to follow Him (Mat 19:18-21).
2.
Yeshua said that the Jewish Scriptures plainly testify of Him (John 5:39). As His followers, we should understand what this means and how they indeed bear witness of Him as the King of the Jews (Mat 2:2; 27:11). In addition, by studying Torah, we can more fully appreciate the glory and grace as revealed in the Person and Work of our beloved Mashiach. For example, we can more fully savor the role of the sacrificial system and how Yeshua fulfilled all of God's holy requirements on our behalf as the Kohen Gadol (High Priest) of the new covenant.
3.
When two disciples were on their way to the town of Emmaus discussing the implications of the crucifixion of Yeshua three days earlier, who but the Master Himself appeared alongside of them and taught them from the Jewish Scriptures? "And beginning with Moses and all the Prophets, he interpreted to them in all the Scriptures the things concerning himself" (Luke 24: 13-36). Again, as His followers, we should likewise be able to recount how Yeshua is revealed in the Jewish Scriptures.
4.
The "Church" was born on a Jewish holiday of Shauv'ot (Pentecost) among the Jewish people in Jerusalem. Peter's sermon during that festival (Acts 2:1-41) was entirely Jewish, copiously quoting from the prophets and David, which would have meant little to any Gentiles in earshot (if there were any). It is likely, therefore, that the 3,000 people who were saved that day would have been all Jewish. The earliest members of the new church met regularly in the Temple, where Gentiles were explicitly excluded (Acts 2:46). Note that the apostles Peter and John are recorded to have gone to the Temple for prayer during the time of the minchah (afternoon) sacrifices (Acts 3:1), and their ministry continued exclusively among the Jewish people, "among whom were thousands who believed and were zealous for the Torah" (Acts 21:20). Even after they were imprisoned but miraculously escaped, an angel told them to "Go, stand and speak in the Temple to the people all the words of this life" (Acts 5:20).
Peter's vision and visit to the house of Cornelius, a ger tzeddek ("God fearer") who attended synagogue and observed Jewish customs and traditions (Acts 10), was subject to a crisis of conscience for him. First, in his vision he said that he never would eat of the "unkosher" animals shown to him, and second, he had qualms about even entering the house of a non-Jew. This indicates, among other things, how steeped Peter was in the Torah, even after spending three years under the teaching of Yeshua.
5.
Later, when the Jerusalem Council wrote their letter to the Gentiles regarding their relationship to the Torah, they advised them to at first abstain from those things that would make them abhorrent to the Jews, with the assumption that they would later go on to study the Torah of Moses and the other Jewish Scriptures (Acts 15:19-21).
6.
The Apostle Paul was raised a Torah observant Jew who studied under the famous Rabbi Gamaliel in Jerusalem (Acts 22:3). Rabbi Sha'ul (as he would have been called) was well-established in the Jewish leadership of his day, and even had a relationship with the Sanhedrin and High Priest of Israel (Acts 9:1-2). But even after his conversion on the road to Damascus (Acts 9:1-21), he still identified himself a Jew. In Acts 23:6 he confessed, "I am (not "was") a Pharisee." He even declared that concerning the observance of the Torah he was "blameless," which indicates that he observed a Jewish lifestyle to his dying day (Phil 3:6). Paul testified that he kept the Torah throughout his life (Acts 25:7-8, see also Acts 28:17).
Paul took the Nazirite vow (Acts 18:18), lived "in observance of the Torah" (Acts 21:23-24), and even offered sacrifices in the Jewish Temple (Acts 21:26). Notice that Paul not only paid for his own sacrifices in order to be released from his Nazirite vow, but also paid for the sacrifices for four other Jewish believers! Notice also that this was performed at the explicit request of James, the head of the Jerusalem Church (and half-brother of Yeshua).
Paul regularly attended synagogue. "He came to Thessalonica, where was a synagogue of the Jews. And Paul, as his manner was, went in unto them, and three Sabbath days reasoned with them out of the Scriptures" (Acts 17:1-2).
When Paul wrote to the Gentile churches, "All Scripture is breathed out by God and profitable for teaching, for reproof, for correction, and for training in righteousness, that the man of God may be competent, equipped for every good work" (2 Tim 3:16-17), he was of course referring to the Jewish Scriptures, since the New Testament had not yet been compiled for the church.
Indeed, in order to understand Paul's writings, we need to remember his training as a Rabbi when he quotes the Scriptures in his writings. For example, when he wrote, "And all drank the same spiritual drink, for they were drinking from a spiritual rock which followed them; and the rock was Christ" (1 Cor. 10:4), he was quoting from a story later written in the Talmud (i.e., that from the time that Moses struck the rock at Horeb and brought forth water until the death of Miriam (Exo 20:1), this water-giving rock "followed the children of Israel through the desert and provided water for them each day" (Taanit, 9a and Bava Metizia, 86b).
7.
Many Christian denominations profess to believe in the authority of both the "Old Testament" and the New Testament Scriptures while functionally relegating the study of the Torah to the dustheap of history. If the Jewish Scriptures are taken seriously at all, these denominational traditions attempt to explain away their clear reading (for example, the covenantal promises made to ethnic Israel) and arrogate the intent of the text as being applicable solely to the Church.
Blessing,
Andre