The Cross
Paul calls the preaching of the cross the power of God unto salvation ( 1 Cor 1:18-21).
Without the cross the gospel is vain, but a trained bloodhound could not find the cross in John 3. Jesus is talking about his origin from heaven in John 3:13 and shows that God sent his Son from heaven into the world in John 3:16. When God “gave his only begotten Son” in John 3:16, he was not speaking about his crucifixion.
The serpent in the wilderness did not die and was lifted up on a pole. The parallel between the serpent and Jesus is that the nation needed to look on them with belief.
The Blood
Speaking of the cross, there is no mention of the blood of Jesus or the forgiveness of sins in John 3 either. Forgiveness of sins is spoken about at other times in Jesus ministry, but John 3 contains neither.
If the gospel is to be preached, ought we not at some point speak about forgiveness through the blood of Jesus Christ?
All this for you to consider that John 3:16 may be too succinct as a gospel verse.
Without the blood, propitiation, or substitutionary atonement, John 3:16 is incomplete regarding the gospel that saves.
The Resurrection
Accompanying the death, blood, and burial of Christ in the gospel that saves is the resurrection of Christ.
John 3:16 is not speaking about resurrection of Christ or anyone else.
If John 3:16 can stand alone as the gospel, are we to neglect this important event? Paul says that if Christ did not raise from the dead, then our preaching is vain (1 Cor 15:14).
It is no coincidence that John 3 is one of only two chapters that speak of being “born again”, and nowhere in the vicinity is the death, blood, or resurrection of Christ.
Both John 3:16 and being “born again” were messages to Israel before the mystery was revealed.
Grace
It is agreed upon by all true Christians that we are saved by the gospel of the grace of God. Without God’s grace through Christ’s finished work by the cross, we are left fending for ourselves where righteousness is concerned.
However, John 3:16 does not say anything about what Jesus did for us, but only who Jesus is. It is true that he is the Son of God, but without his finished work, works were still required within Israel’s covenant system.
This is why Jesus spoke of Israel “doing truth” so that their “deeds may be made manifest” (John 3:21), and two chapters later speaks about their resurrection being contingent on what “they have done” (John 5:29).
God’s abounding grace to the church through the finished work of Christ had not yet been revealed (Eph 3:1-2).
A Good Message … for Nicodemus
John 3:16 is a wonderful verse… if you are Israel looking for your Messiah. It speaks of God’s love, Jesus as the prophesied Christ, and the necessity of belief in Him for everlasting life. It says everything John (and Jesus) intended to identify for Israel who was their Messiah (John 20:31).
It is a tremendous verse to communicate the person of Jesus being Christ, but reducing the gospel we preach today to merely the person of Christ, removes the most important aspect of His finished work. This work had not yet been done, and would not be explained until it was revealed later to the church.
Not every verse or any single verse is required to have all the gospel elements missing from John 3:16, but what is more significant is that the elements above were not the message of Christ at all during his earthly ministry to Israel (Rom 15:8).
The church of today, the gospel for today, and our preaching of Jesus Christ for today was a mystery that had not yet been revealed in Matthew, Mark, Luke, or John. We now know the gospel of Christ that saves through the writings of the apostle Paul in such passages as Romans 3, or succinctly stated in 1 Cor 15:1-4:
“I declare unto you the gospel… by which also ye are saved… how that Christ died for our sins according to the scriptures; And that he was buried, and that he rose again the third day according to the scriptures:” – 1 Corinthians 15:1-4
John 3:16 is a good verse unless you are trying to preach the cross of Christ, the power of God unto salvation. Then, you might consider something in Paul’s epistles like Romans 5:8.