This post answer the questions for the EP Newspaper ad Jan. 31 - Feb. 6.
Is the Old Testament still viable today? And is God different in the Old Testament than the New Testament?
At the time of Jesus, what Scriptures did the Jews have? They had what we call today, the Old Testament. Jesus knew these Scriptures well.
What does Jesus say about the Old Testament Scriptures?
Search the scriptures; for in them ye think ye have eternal life: and they are they which testify of me.
Jesus says right here that the Old Testament Scriptures testified of Him. How? It is estimated that there are around 3,000 prophecies about the Messiah (Jesus). It also revealed aspects about His character and the plan of salvation (through Abraham and through the sanctuary, its feasts, and its services). After His resurrection, Jesus showed His disciples that the Old Testament prophesied these things would happen to Him.
Then beginning with Moses and [throughout] all the Prophets, He went on explaining and interpreting to them in all the Scriptures the things concerning and referring to Himself.
Paul says of the Old Testament Scriptures:
For whatever was thus written in former days was written for our instruction, that by [our steadfast and patient] endurance and the encouragement [drawn] from the Scriptures we might hold fast to and cherish hope.
He also writes in 2 Timothy 3:16-17, speaking about the Old Testament - the only Scriptures available at the time:
"All scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness: That the man of God may be perfect, thoroughly furnished unto all good works" (KJV)
How much of Scripture is profitable for doctrine, reproof, correction, and instructions in righteousness? ALL of it!
In studying the Bible, we find that so much wealth can be gained by using the Old Testament. It brings light to New Testament symbols and concepts. This is especially true when studying the prophecies of Revelation.
What did Jesus say about the God of the Old Testament?
And Jesus said to Philip, "...Have I been with all of you for so long a time, and do you not recognize and know Me yet, Philip? Anyone who has seen Me has seen the Father. How can you say then, Show us the Father?" (John 14:9; AMP).
Here Jesus basically reveals that He is the expression, the visible form of the Father God -- "If you have seen Me, you have seen the Father."
Jesus claimed to be the great I AM - the burning bush that appeared to Moses in Exodus 3:2...
Jesus said to the Jews, “Truly, truly, I say to you, before Abraham was, I am.” So they picked up stones to throw at him, but Jesus hid himself and went out of the temple. John 8:58-59 (NAS)
The reason they were ready to throw stones at Him is because He was making a statement claiming to be God. They understood that God appeared to Moses in the burning bush. By using the same wordage, Jesus is assuming the same title as God. Even implying that it was HE, Himself who appeared to Moses in the burning bush. And that was blasphemy, according to the Biblical definition. They understood that Jesus was claiming to be God and "calling God his own Father, making himself equal with God" (John 5:18).
The disciple John testifies:
And the Word (Christ) became flesh (human, incarnate) and tabernacled (fixed His tent of flesh, lived awhile) among us; and we [actually] saw His glory (His honor, His majesty), such glory as an only begotten son receives from his father, full of grace (favor, loving-kindness) and truth.
No man has ever seen God at any time; the only unique Son, or the only begotten God, Who is in the bosom [in the intimate presence] of the Father, He has declared Him [He has revealed Him and brought Him out where He can be seen; He has interpreted Him and He has made Him known].
Speaking about Jesus, Paul told the Colossians, “ [Now] He is the exact likeness of the unseen God [the visible representation of the invisible]; He is the Firstborn of all creation. ” (Colossians 1:15; AMP).
Jesus is the revelation of God Himself.
So not only is Jesus the revelation of the God of the Old Testament, Jesus upheld the Old Testament Scriptures as divinely authoritative, as the Word of God. Never did He say they were to be cast aside as no longer viable. On the contrary, He said:
Heaven and earth shall pass away, but my words shall not pass away.