Romans 15:12-22
Rom 15:12 (KJV)
And again, Esaias saith, There shall be a root of Jesse, and he that shall rise to reign over the Gentiles; in him shall the Gentiles trust.

(Isa 11:10 KJV) And in that day there shall be a root of Jesse, which shall stand for an ensign of the people; to it shall the Gentiles seek: and his rest shall be glorious. Here we have another passage of prophecy from Isaiah. The idea of God building His church is not only a New Testament truth but it is also seeded throughout the Old Testament. The root of Jesse is the Lord Jesus Christ. Jesse was the father of King David and David was a picture of the Lord Jesus Christ in the Old Testament. So we see that back in Isaiah God had already planned to include the Gentiles in the eternal church. Notice in Isaiah 11:10 it speaks about the rest the Lord will give shall be glorious. This refers to the believers resting in the finished work of the Lord Jesus Christ and the eternal rest which He gives to all His children.

Rom 15:13 (KJV)
Now the God of hope fill you with all joy and peace in believing, that ye may abound in hope, through the power of the Holy Ghost.

Paul here gives a kind word to the Romans. He prays that the God of Hope fills them with joy and peace as they continue to believe in the Lord Jesus Christ. Without believing in the Lord Jesus Christ, there can be no true peace and joy. If one is believing in their theology systems or some religion, their joy will be superficial plus they will never enjoy the true peace that the Lord Jesus gives to His redeemed children. The word “abound” carries with it the meaning of “to prosper.” The true believer will always prosper in the Christian walk because they have the indwelling of the Holy Spirit who fills us with hope, even during the darkest times. The Christian lives the present life in hope. We hope in the resurrection of our bodies. We hope in the promise of heaven. We hope in the soon return of the Lord Jesus Christ. We also hope in God in the present times we live in.

Rom 15:14 (KJV)
And I myself also am persuaded of you, my brethren, that ye also are full of goodness, filled with all knowledge, able also to admonish one another.

Paul is convinced of the true nature of these Roman Christians. Despite the problems they had, they were able to overcome through the power of the Holy Spirit. He believes they are definitely full of goodness and filled with the spiritual knowledge of Christ and because they have the proper knowledge, they will be able to warn or instruct one another, especially in light of the problems that the Roman church had faced. Paul knew that if they just looked to the Lord for guidance, that they would be able to work out all the problems which had plagued the church. Admonishment should come from the brethren and not from outsiders since the brethren in the church would have the knowledge of certain situations.

Rom 15:15 (KJV)
Nevertheless, brethren, I have written the more boldly unto you in some sort, as putting you in mind, because of the grace that is given to me of God,

Boldly - Daring or rash
Sort - Part
Putting you in mind - Reminding them

Paul tells them that he has written to them in a more daring manner than he has to others, at least in parts of the letter. Paul knew the problems of the churches but he was also mindful of the fact that there were many in this church who were more mature so they were able to handle a more firm letter. We can deduce this by reading the passages concerning the treatment of the weaker brethren by those who were the stronger brethren. Paul reminds them that he too is a recipient of the grace of God and that he does not make these assertions in this letter on his own but under the inspiration of the Holy Spirit. So the Holy Spirit would definitely know how tough he needed to get with these Christians so no line would be crossed which would hurt them.

Rom 15:16 (KJV)
That I should be the minister of Jesus Christ to the Gentiles, ministering the gospel of God, that the offering up of the Gentiles might be acceptable, being sanctified by the Holy Ghost.

Paul continues his thread from verse 15 that it is by the grace of God that he was made a minister of the Lord Jesus Christ to the Gentiles. He was a minister of God to the Gentiles that he would offer them up. This means that he would help them become a sacrifice for the kingdom of God but not the type of sacrifice which was found in the Old Testament. Remember in chapter 12, we read that we need to be a living sacrifice and that is what Paul was equipping the Gentile Christians to be. Since these Gentiles had become saved and indwelled by the Holy Spirit, he was helping to make them acceptable. The word “acceptable” carries with it the meaning of “well-received or approved.”
(2 Tim 2:15 KJV) Study to show thyself approved unto God, a workman that needeth not to be ashamed, rightly dividing the word of truth. Do you remember in Chapter 15:4, how we are to study those Scriptures so we are to know what we are to do? Well the 2 Timothy passage confirms that teaching in Romans here that we must study to also become the workman of God that will not be ashamed. We can be ashamed when we walk around with a big Bible under our arms and not know the contents of it. Unfortunately, that is the major situation in today’s churches.

Rom 15:17 (KJV)
I have therefore whereof I may glory through Jesus Christ in those things which pertain to God.

Paul knew that he could glory, but only in the Lord Jesus Christ. Galatians 6:14 teaches us that we are to glory in the cross of Christ. In of ourselves we do not have anything to glory about. The cross of Christ definitely pertains to the things of God because it was God who engineered the sacrifice of Christ to save the Elect which He named before the foundation of the world. We can also glory in the things which God has done for us in this life and the hope He offers for the next life. Any Christian who glories in themselves is a self-worshipper and has an arrogant spirit and can expect God to chastise them to bring them back to reality.

Rom 15:18 (KJV)
For I will not dare to speak of any of those things which Christ hath not wrought by me, to make the Gentiles obedient, by word and deed,

Paul knew that he was a person in the hands of Christ and he would not bring into any situation the things which he had done, instead he always exalted Christ and what Christ had done. You never hear Paul speaking as we hear so many today brag that Christ used me to do this or I did that or this. We see in the life of the Apostle Paul that he always set about to glorify the Lord Jesus Christ. Anything which Paul accomplished, whether in word or deed, he attributed it to the Lord Jesus Christ. By speaking in those terms, the Gentiles learned the truth about Christ. People will never learn the truth about Christ when the one preaching is always talking about themselves. The people will learn about the preacher and will remain ignorant about the Lord Jesus. Unfortunately, this seems to be the overriding situation in the churches and in ministry today.

Rom 15:19 (KJV)
Through mighty signs and wonders, by the power of the Spirit of God; so that from Jerusalem, and round about unto Illyricum, I have fully preached the gospel of Christ.

The same God who parted the Red Sea and performed the ten plagues on the Egyptians had uses signs in the early church to confirm the word that the Apostles were teaching were from God.
(Mark 16:20 KJV) And they went forth, and preached every where, the Lord working with them, and confirming the word with signs following. Amen. The reason that miracles were performed in the early church were to confirm the word which was being preached. The miracles had waned by the end of the first century with the completion of the Bible in 95 AD. Paul makes sure that his readers know that it was not him performing the miracles but it was the power of the Spirit of God who did it. Paul also tells them that he had preached the Gospel in Jerusalem and even to the place of Illyricum. Illyricum was about 1,000 miles from Jerusalem and was situated northwest of Macedonia and directly east of Italy. He states that he has fully proclaimed the Gospel of Christ to all these areas and in between.

Rom 15:20 (KJV)
Yea, so have I strived to preach the gospel, not where Christ was named, lest I should build upon another man's foundation:

Paul’s desire was to preach in virgin territory where the Gospel was never preached before. His desire was to reach the areas which were not yet reached with the Gospel. This is the true missionary spirit in that he wanted to bring the Gospel to the Gentiles in different parts of the world, this way centers of evangelism could be formed and then the Gospel sent out from there by other brethren whom the Lord saved. Paul did not want to bring the Gospel in an area where there was already a Gospel work going on because he did not want it to seem he was trying to build on another’s work. He wanted to see the widest distribution of the Gospel as possible which meant that he was going to different places where the Gospel was not yet proclaimed. This is why God gives us different ministries because one person may be able to reach a group that another person cannot.
Rom 15:21 (KJV)
But as it is written, To whom he was not spoken of, they shall see: and they that have not heard shall understand.

(Isa 52:15 KJV) So shall he sprinkle many nations; the kings shall shut their mouths at him: for that which had not been told them shall they see; and that which they had not heard shall they consider. Paul uses this verse from Isaiah to give understanding why he was preaching the Gospel in the places where no one had ever preached the Gospel before. This verse teaches us that there will be Elect in all those different places and that is why the Gospel must go out throughout the whole world and not just in populated places. When the Gospel is proclaimed, those who never heard, who are the Elect of God, will understand once they have become saved. It will be fulfillment of the prophecy from Isaiah.

Rom 15:22 (KJV)
For which cause also I have been much hindered from coming to you.

It was for the reason of Paul spending much time preaching the Gospel which has hindered him from paying a personal visit to the Roman Christians. Paul was like Nehemiah, he knew the task he had at hand at that time which had to be completed and nothing was to divert him from the goal of preaching the Gospel to those who never heard it. The true preacher of the Gospel is sold out to the preaching of the Gospel and that is the attitude which we must take in these last days. The things of the world need to take a back seat to the proclamation of the Gospel.