K008. The gospel that Jesus preached is the gospel of the kingdom of God

It is the gospel of grace because it is given by grace. It did not came by the law or Moses; it came by Jesus Christ:
Joh 1:17 KJV  For the law was given by Moses, but grace and truth came by Jesus Christ.

But many argue, If the kingdom of God is given by grace or came by grace, we should do nothing and can do nothing for it. I will tell them, Of course, we can do something and should do something; or else Jesus would not tell us to do something and seek for it:
Mat 6:33-34 KJV  But seek ye first the kingdom of God, and his righteousness; and all these things shall be added unto you..
Mar 1:14-15 KJV  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.

Let me give you an example: If you commit a traffic offence today, the police may give you a ticket of summon for you to pay the fine. Do you know that you must do something (pay the fine) within the grace period? Don't you think that the ticket of summon could also be a 'type of grace' which is given for all the traffic offenders to pay their fines, learn their mistakes, and continue to drive on the roads? I know that this is a bad analogy. But Jesus gave us a better picture of how the kingdom of God is like:
Luk 13:2-9 KJV  And Jesus answering said unto them, Suppose ye that these Galilaeans were sinners above all the Galilaeans, because they suffered such things?  (3)  I tell you, Nay: but, except ye repent, ye shall all likewise perish .. (6)  He spake also this parable; A certain man had a fig tree planted in his vineyard; and he came and sought fruit thereon, and found none.  (7)  Then said he unto the dresser of his vineyard, Behold, these three years I come seeking fruit on this fig tree, and find none: cut it down; why cumbereth it the ground?  (8)  And he answering said unto him, Lord, let it alone this year also, till I shall dig about it, and dung it:  (9)  And if it bear fruit, well: and if not, then after that thou shalt cut it down.
Do you notice the word 'also' in (v6) above? it means that the parable given was related to His command for the sinners to repent; or else they would all likewise perish, irrespective of whether they are more righteous than others or they feel that they are more righteous.

Hence, the gospel that Jesus preached is not just the gospel for the sinners or the believers to feel more righteous or to think of more grace for more sins in life. The gospel that Jesus preached has 'grace limits'. After knowing and receiving the kingdom of God by grace, we should be more diligent in life. Take for example: If you have  known more about the traffic rules after receiving the summon tickets, will you drive more recklessly on the roads or will you drive more cautiously? Similarly, if we have really known the kingdom of God, we would not go around and boast about how much grace we  can get from God (or the number of traffic tickets we can receive on the roads); instead, we  would live more diligently and warn others with the gospel that Jesus preached or the gospel of the kingdom of God. 
2Pe 3:9-14 KJV  The Lord is not slack concerning his promise, as some men count slackness; but is longsuffering to us-ward, not willing that any should perish, but that all should come to repentance .. (13) Nevertheless we, according to his promise, look for new heavens and a new earth, wherein dwelleth righteousness.  (14)  Wherefore, beloved, seeing that ye look for such things, be diligent that ye may be found of him in peace, without spot, and blameless.

The gospel of the kingdom through Jesus is the end time gospel
Mat 24:14 KJV  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.

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