Your verse is teaching the "gospel of the Kingdom" and that is because Jesus was on Earth, He had come.
He's not here now, so, that Gospel is not the Body of Christ Gospel.,, which is the one that Paul gave us.
Its the one that has Jesus on the Cross shedding His blood for your sin.
You wont find Jesus preaching that one to the Jews in your verse, as He had not died on the Cross yet, so that Gospel, (Paul's) was not available yet.
You cannot claim Jesus’ gospel ended when He left the earth, because He Himself said, “The words that I speak unto you, they are spirit, and they are life” (John 6:63, KJV). He also said, “He that believeth on me hath everlasting life” (John 6:47, KJV). Life has never depended on a later letter or a new teacher—it has always depended on faith in Him and obedience to God.
Jesus made it clear that His teaching is eternal: “Think not that I am come to destroy the law, or the prophets: I am not come to destroy, but to fulfil. For verily I say unto you, Till heaven and earth pass, one jot or one tittle shall in no wise pass from the law, till all be fulfilled” (Matthew 5:17–18, KJV). His words reveal sin, guide righteousness, and lead to life. Sin brings death, not the law, as He said: “For out of the heart proceed evil thoughts… these are the things which defile a man” (Matthew 15:19–20, KJV).
Salvation has always been offered through Him. and no one else. He calls everyone: “Come unto me, all ye that labour and are heavy laden, and I will give you rest” (Matthew 11:28, KJV). He tied love and obedience together: “If ye love me, keep my commandments” (John 14:15, KJV). He is eternal: “Jesus Christ the same yesterday, and today, and forever” (Hebrews 13:8, KJV).
To claim that the gospel changed, or that His words are now secondary to someone else’s letters, is to place another above the Master. The student is never greater than the teacher, and no servant is above the Lord (Matthew 10:24, KJV). Jesus’ gospel is alive today, just as it was when He walked the earth. It is complete, eternal, and sufficient for salvation. Anything else that claims to replace it is already outside the truth Jesus Himself taught.
