How are the two main parts of the Bible related to each other?

Answer 1

In a general sense, the Old Testament (also called the Hebrew Scriptures) is the history of mankind and their relationship with God.

It starts out in the beginning, when God turned his attention to the earth and began creating something special on it.

When man rebels and sins, then God makes a promise (Genesis 3:15) to put into place a means by which mankind can be redeemed from the initial sin that Adam committed (which condemned mankind to sin and death). He promises a "seed" that will take away the sins of the world.

As this promise unfolds, God makes covenants with several individuals along the way that their descendants would be part of this promised "seed". These individuals included Abraham, Jacob & David.

Keeping track of the family lineage was very important so that the "seed" could be traced back to these individuals.

This promise also included the formation of the nation of Israel (through Jacob) and the establishment of the Mosaic Law. (Genesis - Deuteronomy).

But the Law had an end point - the arrival of the promised seed.

Jesus was the Messiah that "fulfilled" the purpose of the Law - the opportunity for redemption. (Romans 10:4)

So, next we have the New Testament (also called the Greek Scriptures).

The New Testament covers the life of Jesus Christ, the growth of the early Christian congregation and ends with the prophecyabout the last days of humankind under Adam's sin and how Jesus Christ will then take action to reverse all the effects of humankind's sin and fulfill his assignment.

See related links for interesting articles on what's in The Bible.

Note: Some feel that when Jesus instituted a "new covenant" with his Apostles, that this was the reason for the use of "Old Testament" and "New Testament"

(Luke 22:19, 20) 19 Also, he took a loaf, gave thanks, broke it, and gave it to them, saying: "This means my body which is to be given in YOUR behalf. Keep doing this in remembrance of me." 20 Also, the cup in the same way after they had the evening meal, he saying: "This cup means the new covenant by virtue of my blood, which is to be poured out in YOUR behalf.

Citations:

(Genesis 3:15) And I shall put enmity between you and the woman and between your seed and her seed. He will bruise you in the head and you will bruise him in the heel."

(Romans 10:4) 4 For Christ is the end of the Law, so that everyone exercising faith may have righteousness.

Another answer:

Jesus tells us that the "Old Testament" PROPHESIED of Him:

"...When I was with you before, I told you that EVERYTHING WRITTEN ABOUT ME by Moses and the prophets and in the Psalms MUST ALL COME TRUE." (Luke 24:44 NLT New Living Translation)

And in the "New Testament" we see the FULFILLMENT of the Old Testament prophecies beginning to take place... culminating with the eventual return of Christ to the earth for the final stages of fulfilling all of the prophecies on the "Last Great Day" of God's plan... Judgment Day.

The New Testament also brings to light the "Spiritual" aspect of the Old Testament laws.

"You have heard that the law of Moses [the Old Testament] says, 'Do not murder. If you commit murder, you are subject to Judgment. But I say, IF YOU ARE ANGRY WITH SOMEONE [Jesus' illuminating New Testament application of the SPIRITUAL STAGE IN ONE'S HEART PRIOR TO the Old Testament physical manifestation of murder], you are subject to Judgment..." (Matt.5:21-22 NLT).

A case of "duality" exists throughout the Bible. The "Old and New Testaments" are one example of this. The Bible speaks of two deaths... two births... two resurrections... the two sexes, male and female God created... the DUALITY OF GOD: ["...THE FATHER AND I ARE ONE." - John 10:30 NLT], etc. And there is the "material" and the "spiritual" aspects of creation that's contrasted between the two testaments.

"...For just as there are naturalbodies, so also there are spiritualbodies... What came first was the natural body, then the spiritual body comes later. Adam, the first man [Old Testament], was made from the dust of the earth, while Christ [New Testament], the Second Man, came from heaven. Every human being has an earthly body just like Adam's, but our heavenly bodies will be just like Christ's. Just as we are now like Adam, the man of the earth, so we will someday be like Christ, the Man from heaven." (I Cor.15:44-49 NLT)

The New Testament brings the spiritual aspects of God's material creation [Old Testament] full circle... and COMPLETES God's Testimony.

"Bind up the testimony, SEAL[complete] the law among My disciples." (Isa.8:16 KJV)