I meet quite a few Christians who do not bother to read or study the Old Testament. The common reason I hear is that Jesus came and did away with the old covenant. In a spiritual sense that’s true, but really its not.
Jesus, as a Jewish man, learned and followed Jewish customs & traditions, picked Jewish men and was sent to that nation(Matthew 15:24 & Matthew 10:5-7 & John 4:22). Paul’s ministry was sent to the gentile nation (Acts 28:28 & Galations 2:7-8 & Ephesians 3:6 & Acts 22:21) . In Order to understand many sayings, works, and foundations of Jesus, reading of the Old Testament (Tanakh or Hebrew Bible) is necessary.
Its sad to see so many lost because of the lack of knowledge of the Holy Scriptures, which is filled with instruction, blessings, and curses–yes curses if we do certain things. If you wonder why certain things are not going forth, you might want to check to see if God Himself has cursed you based on some actions you must repent of & eliminate from your life.
Historical references, predictions, guidance, and allusions are made throughout the whole Bible and not just half of it. When we accept Christ, we become part of the Israel family. So I think it would assist us to know the type of relationship He had/has with them. Following His Law, doesn’t make us to work for salvation, but instead proves how much we need His grace!