Acts 20:17-24,32 KJV
 And from Miletus he sent to Ephesus, and called the elders of the church.  And when they were come to him, he said unto them, Ye know, from the first day that I came into Asia, after what manner I have been with you at all seasons,  Serving the Lord with all humility of mind, and with many tears, and temptations, which befell me by the lying in wait of the Jews:  And how I kept back nothing that was profitable unto you , but have shewed you, and have taught you publicly, and from house to house,  Testifying both to the Jews, and also to the Greeks, repentance toward God, and faith toward our Lord Jesus Christ.  And now, behold, I go bound in the spirit unto Jerusalem, not knowing the things that shall befall me there:  Save that the Holy Ghost witnesseth in every city, saying that bonds and afflictions abide me.  But none of these things move me, neither count I my life dear unto myself, so that I might finish my course with joy, and the ministry, which I have received of the Lord Jesus, to testify the gospel of the grace of God.
 And now, brethren, I commend you to God, and to the word of his grace, which is able to build you up, and to give you an inheritance among all them which are sanctified.
The Gospel of our Lord Jesus Christ is the gospel of grace. It was the grace of God that made Paul an effective minister. Our lives challenges and challenges in ministry can be surmount by God’s grace. Paul prayed to the Lord when he was tormented and had thorn in his flesh and the Lord assured him that His grace is sufficient and His power is made perfect in weakness.
2 Corinthians 12:7-9 KJV
 And lest I should be exalted above measure through the abundance of the revelations, there was given to me a thorn in the flesh, the messenger of Satan to buffet me, lest I should be exalted above measure.  For this thing I besought the Lord thrice, that it might depart from me.  And he said unto me, My grace is sufficient for thee: for my strength is made perfect in weakness. Most gladly therefore will I rather glory in my infirmities, that the power of Christ may rest upon me.
The grace of God is more than any medicine any doctor can prescribe for you. Paul always testify to the grace of God whenever he preached the Gospel because he had experienced it in so many areas of his life. Paul used his lifestyle as an example to the elders in his farewell because his life has been transparent to them having lived among them for two years.
His message was his life and his testimony was that he had served God with all his heart despite the provocation by those who were against him.
We all have people facing different challenges around us but our testimonies of God’s grace can change their situation. Just like Paul did not hesitate to preach anything that will help the Ephesian elders to grow spiritually, we as Christian also should not hesitate to preach what will help the people around us grow in faith.
Paul taught them publicly, from house to house, declaring that both Jews and Gentiles must turn to God in repentance and have faith in God. So also we must teach people publicly, doing house to house witnessing telling people around us to turn to God and have faith in God.
You need to take note that you cannot preach the grace if your life is void of the grace of God. We need to work hard to complete the task ahead of us. Your testimony will be great if you do the work of God.
I pray our testimony will give healing to the broken hearted in Jesus Name. Amen