The Gospel (good news) is the Gospel Of Jesus Christ so it is the good news about Jesus the Messiah.   

What is that good news?   It depends on who Jesus is, what He said and what He did.   

If Jesus is just another human being who lived and said and did some good things then He should be honored for His contributions to humanity.   

But Jesus did not claim to be a good man.   He claimed to be the Son Of Man.   He claimed to be Saviour.   He claimed to have all power in heaven and earth.   

Now, anyone who makes claims that are false is not only not a good man, but he is a liar.   

So, the main issue with respect to Jesus has to do with His veracity.   Can we believe what He said about Himself and can we believe what His disciples said about Him?   

The Gospel is only good news if it is true.   Otherwise, it is just a fairy tale.   

As mentioned above there are many different opinions about who Jesus was.   Our opinions of Jesus are only valid if they are the Truth.   And, yes, Jesus claimed to be the Truth.   

The Truth about what?   

The Truth about existence.   

The fact that we exist is not sufficient for human beings.   We want to know how all this came to be and is there a purpose in it all?   

Jesus is the Truth that answers all our existential questions.   

But, is He just the messenger of God?   

Before answering that question we must first be clear on what we mean by 'God'.   God is:
   ➛ Supreme
   ➛ Designer
   ➛ Creator
   ➛ Law giver that orders
   ➛ Power that upholds
   ➛ Judge that evaluates

Let's assume that Jesus is just the messenger of God but not God Himself.   Well, right off the bat we must reject Jesus as He said that He, Jesus, had all power in heaven and earth.   On top of that He said that He and His Father are One and that to look upon Jesus is to look upon the Father.   

So, either you must reject Jesus as being Truth or recognize that He is not only truthful but that He is God.   

So, point number one about Jesus being the Truth is that Jesus is God.   

Because Jesus is God, He has the authority to forgive sins and He has the authority to give Eternal Life.   

So, the Good News ( Gospel) is that God came
   ➛ to live among us,
   ➛ to speak to us,
   ➛ to heal us,
   ➛ to forgive us
   ➛ to impart to us Eternal Life
   ➛ to be One with us.   

Jesus is Creator, Saviour, Lord and King of all creation and of each of us personally who believe on Him.   

   ➛ He is the Righteous Judge
   ➛ He is the Alpha And Omega
   ➛ He is the Ancient Of Days
   ➛ He is King Of Kings
   ➛ He is Lord Of Lords
   ➛ By His name and only His name is anyone saved.   

All those whose names are not in His Book Of Life will be cast into the Lake Of Fire.   

All those whose names are in His Book Of Life will never know death but will enjoy eternity in His presence with all the benefits of being in an intimate personal relationship with Him.   

Get to know Jesus personally by diving into His Word and His Holy Spirit.   

But what things were gain to me, those I counted loss for Christ. Phi 3:7 Paul understood that those accomplshments stood in the way for his receiving the Fulness Of Christ.

Yes doubtless, and I count all things but loss for the excellency of the knowledge of Christ Jesus my Lord: for whom I have suffered the loss of all things, and do count them but dung, that I may win Christ, Phi 3:8 So, he wilfully and purposely discounted all his accomplishments so that he could pursue the excellency of the knowledge of Christ.      His winning of Christ was simple but not necessarily easy - he had to give up his Self Righteousness and receive the righteousness by faith.

And be found in him, not having my own righteousness, which is of the law, but that which is through the faith of Christ, the righteousness which is of His Holy Spirit by faith: Phi 3:9 Note that the place where believers exist is In Christ Jesus.     Since Jesus is a physical being the only way we can be In Christ is when we are in His Holy Spirit and His Holy Spirit is in us.      It was His love that led the Holy Spirit to make Himself a body to be the sacrifice for our sins so that we can be in intimate personal relationship with Him.      In coming into us and us into Him we have His righteousness and His life.     It is all a free gift that we receive by faith in the Gospel of Jesus Christ.      The Faith Of Christ is our anchor.     We trust in Him    ➛ who He is    ➛ what He said    ➛ what He did and thereby we are found in Him.

That I may know him, and the power of his resurrection, and the fellowship of his sufferings, being made conformable unto his death; Phi 3:10 We can only know Christ through spending time with Him - listening to Him and meditating on His words Joh 5:39 Joh 8:31.      The Power of His resurrection eliminates fear Heb 2:15.      In this fearlessness we are able to testify of Him to every man and so come to experience rejection, hatred and persecution Mat 24:9.      Such knowledge, power and sacrifice makes us conformable unto His death.     We are living sacrifices Rom 12:1.      The world that Paul lived in needed Him as such.     The world that we live in is no different.      When we deny ourselves and share the Gospel of Christ Jesus we enter into a level of fellowship with Him that those who do not submit never experience.