Purpose of Jesus
Because all of us had sinned, we are condemned to death. However, Jesus love us enough to reconciled us with His Father at the crucifixion.
For the Son of man is come to seek and to save that which was lost. -- Luke 19:10 (ESV)
Because...
“As the Father loved me, I also have loved you; abide in my love.” -- John 15:9 (NKJV)
Therefore...
Jesus said to him,
"I am the way, and the truth, and the life. No one comes to the Father except through me."
-- John 14:6 (ESV)
The way
Jesus was not intended to be the final destination, but instead he is "the way" to God.
This is good, and it is pleasing in the sight of God our Savior, who desires all people to be saved and to come to the knowledge of the truth. For there is one God, and there is one mediator between God and men, the man Christ Jesus, who gave himself as a ransom for all, which is the testimony given at the proper time. -- 1 Timothy 2:3-6 (ESV)
and
For through him (Jesus) we both have access in one Spirit to the Father.
So then you are no longer strangers and aliens, but you are fellow citizens with the saints and members of the household of God.
-- Ephesians 2:28-19 (ESV)
Peter said:
For Christ also suffered once for sins, the righteous for the unrighteous, that he might bring us to God, being put to death in the flesh but made alive in the spirit... -- 1 Peter 3:18 (ESV)
The truth
Teach the kingdom of God
And when it was day, he (Jesus) departed and went into a desolate place. And the people sought him and came to him, and would have kept him from leaving them, but he said to them,
“I must preach the good news of the kingdom of God to the other towns as well; for I was sent for this purpose.”
And he was preaching in the synagogues of Judea.
-- Luke 4:42-44 (ESV)
Which was Nicodemus witness:
Now there was a man of the Pharisees named Nicodemus, a ruler of the Jews. This man came to Jesus by night and said to him,
“Rabbi, we know that you are a teacher come from God, for no one can do these signs that you do unless God is with him.”
-- John 3:1-2 (ESV)
This was also confirmed by Paul:
To me, though I am the very least of all the saints, this grace was given, to preach to the Gentiles the unsearchable riches of Christ, and to bring to light for everyone what is the plan of the mystery hidden for ages in God Who created all things, so that through the church the manifold wisdom of God might now be made known to the rulers and authorities in the heavenly places.
This was according to the eternal purpose that He has realized in Christ Jesus our Lord, in whom we have boldness and access with confidence through our faith in him.
-- Ephesians 3:8-12 (ESV)
And the author of Hebrews:
Long ago, at many times and in many ways, God spoke to our fathers by the prophets, but in these last days He has spoken to us by His Son... -- Hebrews 1:1-2 (ESV)
Bear witness to the truth
Jesus answered, “My kingdom is not of this world. If my kingdom were of this world, my servants would have been fighting, that I might not be delivered over to the Jews. But my kingdom is not from the world.”
Then Pilate said to him, “So you are a king?”
Jesus answered, “You say that I am a king. For this purpose I was born and for this purpose I have come into the world: to bear witness to the truth. Everyone who is of the truth listens to my voice.”-- John 18:36-37 (ESV)
To fulfill prophecies
Do not think that I have come to abolish the Law or the Prophets; I have not come to abolish them but to fulfill them. For truly, I say to you, until heaven and earth pass away, not an iota, not a dot, will pass from the Law until all is accomplished. -- Matthew 5:17-18 (ESV)
and
Then he (Jesus) said to them, “These are my words that I spoke to you while I was still with you, that everything written about me in the Law of Moses and the Prophets and the Psalms must be fulfilled.”
Then he opened their minds to understand the Scriptures, and said to them, “Thus it is written, that the Christ should suffer and on the third day rise from the dead, and that repentance and forgiveness of sins should be proclaimed in his name to all nations, beginning from Jerusalem. You are witnesses of these things.
-- Luke 24:44 (ESV)
The life
But as he considered these things, behold, an angel of the Lord appeared to him in a dream, saying, “Joseph, son of David, do not fear to take Mary as your wife, for that which is conceived in her is from the Holy Spirit. She will bear a son, and you shall call his name Jesus, for he will save his people from their sins.” -- Matthew 1:20-21 (ESV)
A few years later...
Truly, truly, I say to you, unless a grain of wheat falls into the earth and dies, it remains alone; but if it dies, it bears much fruit. Whoever loves his life loses it, and whoever hates his life in this world will keep it for eternal life. If anyone serves me, he must follow me; and where I am, there will my servant be also. If anyone serves me, the Father will honor him.
Now is my soul troubled. And what shall I say? ‘Father, save me from this hour’?
But for this purpose I have come to this hour. Father, glorify Your name.”
Then a voice came from heaven: “I have glorified it, and I will glorify it again.”
The crowd that stood there and heard it said that it had thundered.
Others said, “An angel has spoken to him.”
Jesus answered, “This voice has come for your sake, not mine. Now is the judgment of this world; now will the ruler of this world be cast out. And I, when I am lifted up from the earth, will draw all people to myself.”
He said this to show by what kind of death he was going to die.
So the crowd answered him, “We have heard from the Law that the Christ remains forever. How can you say that the Son of Man must be lifted up? Who is this Son of Man?”
So Jesus said to them, “The light is among you for a little while longer. Walk while you have the light, lest darkness overtake you. The one who walks in the darkness does not know where he is going. While you have the light, believe in the light, that you may become sons of light.”
-- John 12:24-36 (ESV)
Good deeds cannot save:
If righteousness were through the law, then Christ died for no purpose. -- Galatians 2:21 (ESV)