Jesus's Gospel.. the original Gospel.
Matthew 24:11 And many false prophets shall rise, and shall deceive many. 12 And because iniquity shall abound, the love of many shall wax cold. 13 But he that shall endure unto the end, the same shall be saved. 14 And this GOSPEL OF THE KINGDOM shall be preached in all the world for a witness unto all nations; and then shall the end come.
Luke 16:15 And he said unto them, Ye are they which justify yourselves before men; but God knoweth your hearts: for that which is highly esteemed among men is abomination in the sight of God. 16 The law and the prophets were until John: since that time the kingdom of God is preached, and every man presseth into it.
Luke 4:43 And he said unto them, I must preach the kingdom of God to other cities also: for therefore am I sent.
Mark 1:14 Now after that John was put in prison, Jesus came into Galilee, preaching the gospel of the kingdom of God, 15 And saying, The time is fulfilled, and the kingdom of God is at hand: repent ye, and believe the gospel.
Matthew 4:23 And Jesus went about all Galilee, teaching in their synagogues, and preaching the gospel of the kingdom...
etc.
Paul
Acts 19:8 He (Paul) went into the synagogue, and spake boldly for the space of three months, disputing and persuading the things concerning the Kingdom of God
Acts 28:23 He expounded and testified the kingdom of God, persuading them concerning Jesus, both out of the law of Moses, and out of the prophets