Most Christians I meet embrace only the most popular teachings from the New Testament, but ignore all of the embarrassing passages from the Old Testament, all the while claiming that the Bible is the most important book in the world.
This site reminds Christians that Jesus himself embraced all the Old Testament.
1) “For truly, I say to you, till heaven and earth pass away, not an iota, not a dot, will pass the law until all is accomplished. Whoever then relaxes one of the least of these commandments and teaches men so, shall be called least in the kingdom of heaven; but he who does them and teaches them shall be called great in the kingdom of heaven.” (Matthew 5:18-19 RSV) Clearly the Old Testament is to be abided by until the end of human existence itself. None other then Jesus said so.
2) All of the vicious Old Testament laws will be binding forever. “It is easier for Heaven and Earth to pass away than for the smallest part of the letter of the law to become invalid.” (Luke 16:17 NAB)
3) Jesus strongly approves of the law and the prophets. He hasn’t the slightest objection to the cruelties of the Old Testament. “Do not think that I have come to abolish the law or the prophets. I have come not to abolish but to fulfill. Amen, I say to you, until heaven and earth pass away, not the smallest part or the smallest part of a letter will pass from the law, until all things have taken place.” (Matthew 5:17 NAB)
3b) “All scripture is inspired by God and is useful for teaching, for refutation, for correction, and for training in righteousness…” (2 Timothy 3:16 NAB)
3c) “Know this first of all, that there is no prophecy of scripture that is a matter of personal interpretation, for no prophecy ever came through human will; but rather human beings moved by the holy Spirit spoke under the influence of God.” (2 Peter 20-21 NAB)
4) Jesus criticizes the Jews for not killing their disobedient children according to Old Testament law. Mark.7:9-13 “Whoever curses father or mother shall die” (Mark 7:10 NAB)
5) Jesus is criticized by the Pharisees for not washing his hands before eating. He defends himself by attacking them for not killing disobedient children according to the commandment: “He that curseth father or mother, let him die the death.” (Matthew 15:4-7)
6) Jesus has a punishment even worse than his father concerning adultery: God said the act of adultery was punishable by death. Jesus says looking with lust is the same thing and you should gouge your eye out, better a part, than the whole. The punishment under Jesus is an eternity in Hell. (Matthew 5:27)
7) Peter says that all slaves should “be subject to [their] masters with all fear,” to the bad and cruel as well as the “good and gentle.” This is merely an echo of the same slavery commands in the Old Testament. 1 Peter 2:18
8) “Did not Moses give you the law, and yet none of you keepeth the law” (John7:19) and “For the law was given by Moses,…” (John 1:17).
9) “…the scripture cannot be broken.” –Jesus Christ, John 10:35