Answer: We should be careful to do what is right in the eyes of everybody, (verse 17).
MORE INFORMATION AND/OR OTHER SCRIPTURE REFERENCES:
Proverbs 3:3-4: "Let love and faithfulness never leave you; bind them around your neck, write them on the tablet of your heart. Then you will win favor and a good name in the sight of God and man."
Again, Christians are Christians ALL of the time. The transformation of conforming to Christ is a constant, never-ending endeavor, which is fervently PERSUED by God's child. The teachings of the Gospel are lived in the DAILY life of the believer. If a Christian's speech and actions are the same as the world they have been separated from through the blood of Jesus, then they are not truly IN Christ. If a Christian betrays the high moral standards of the Gospel in daily life (home, work, school, recreation--whatever), then that "Christian" has NOT reflected the glory of God to the world, nor has that "Christian" brought glory TO God.
The one who claims to be a Christian and then proceeds to act in all ways just as the world does only brings the Gospel of Christ into disrepute. And he causes unbelievers to look with disdain, contempt and scorn upon one who says he is a follower of Jesus, and upon Jesus Himself. Instead of drawing unbelievers TO Christ, this type of person will cause unbelievers to reject any idea in their hearts and minds of seeking Christ.
Christians who are "careful to do what is right in the eyes of everybody" are not serving "everybody." They are serving God. "Everybody" then reaps the benefits of God, reflected in His child. When a Christian is "careful to do what is right in the eyes of everybody," that Christian is only doing what is right in the eyes of God, as he is taught to do in the Word of God. He is simply living out a Spirit-filled life, and "everybody" can see this life, and can see the glory of God in this life.
This, then, GIVES glory to God before all people. God, then, proudly displays His children to the world as a "triumphal procession" in Christ, and He uses us to spread the sweet knowledge of Him (the Gospel of Christ). To God, His children, who are daily transforming themselves by the knowledge of God to be more and more like Christ, are the sweet aroma of Christ. God breathes in His children as His children breathe out in "living Words" the Good News of His Son. The aroma of God's children is breathed in by fellow Christians to strengthen the body of Christ with the fragrance of life eternal, and it is breathed in by those who are perishing. Those who are perishing will either hate us for being a constant reminder that they are living in the darkness and death of sin, or they will be influenced by our radiant light and sweet fragrance of Christ to turn to repentance:
2 Corinthians 2:14-17: "But thanks be to God, Who always leads us in triumphal procession in Christ and through us spreads everywhere the fragrance of the knowledge of Him. For we are to God the aroma of Christ among those who are being saved and those who are perishing. To the one we are the smell of death; to the other, the fragrance of life. And who is equal to such a task? Unlike so many, we do not peddle the Word of God for profit. On the contrary, in Christ we speak before God with sincerity, like men sent from God."
As far as "who is equal to such a task?", God's children are equal to the task of this "spreading everywhere the fragrance of the knowledge of Him." We do it by "being careful to do what is right in the eyes of everybody," whether in our teaching or in the actions of our daily lives. We do it, not by ourselves, but with the competence GOD gives to His children through the knowledge of His Word, which we study daily AND put into our lives. We ourselves become like an open letter from Christ to the world. He did not write our letter in ink, but He wrote it with the Spirit of the living God on the tablets of our hearts.
In 2 Corinthians 3:1-6, Paul is writing to fellow Christians. Some of these Christians were trying to cause divisions in the church, the body of Christ, by saying that Paul needed a "letter of recommendation" so that the church might not doubt that He was an apostle of Jesus Christ. These "Christians" wanted to destroy Paul's work as a minister of the Gospel. Paul says, "Are we beginning to commend ourselves again? Or do we need, like some people, letters of recommendation to you or from you? You yourselves are our letter, written on our hearts, known and read by everybody. You show that you are a letter from Christ, the result of our ministry, written not with ink but with the Spirit of the living God, not on tablets of stone but on tablets of human hearts. Such confidence as this is ours through Christ before God. Not that we are competent in ourselves to claim anything for ourselves, but our competence comes from God. He has made us competent as ministers of a new covenant--not of the letter but of the Spirit; for the letter kills, but the Spirit gives life."
And Christians live this life by "being careful to do what is right in the eyes of everybody."
In 2 Corinthians 8:16-21, Paul speaks of a "brother"--a fellow member of the family of God--who was going with Titus (a minister or preacher or evangelist, of the Gospel) to Jerusalem with an offering collected from many congregations of the Lord's people. The offering was being carried to Jerusalem to help the poor saints (Christians) there. Notice what Paul says about the "brother" and what he says about the offering itself, and about their handling of the offering:
"I thank God, Who put into the heart of Titus the same concern I have for you. For Titus not only welcomed our appeal, but he is coming to you with much enthusiasm and on his own initiative. And we are sending along with him the brother who is praised by all the churches for his service to the Gospel. What is more, he was chosen by the churches to accompany us as we carry the offering, which we administer in order to honor the Lord Himself and to show our eagerness to help. We want to avoid any criticism of the way we administer this liberal gift. For we are taking pains to do what is right, not only in the eyes of the Lord but also in the eyes of men."
This "being careful to do what is right in the eyes of everybody" or "taking pains to do what is right" in the eyes of God and men is one of the qualifications to be an elder (also called, among other things, an "overseer" and "shepherd" and "bishop") in a congregation of the Lord's people as stated in 1 Timothy 3:7:
"He must also have a good reputation with outsiders, so that he will not fall into disgrace and into the devil's trap."
The life that Jesus gave to us is being revealed by us in our bodies. This is what people see as they observe our daily lives. They see the death of the old person of sin, and the life from Christ in the "new creation," a life doing what is right at all times, not for the sake of the praises of men, but for the sake of our complete love and devotion to the Life-giver, Jesus Christ, and the Father, Who sent Jesus to us.
Even as we are daily "dying" physically, we are ALIVE in Christ. To a world of unbelievers who are dying physically and are already dead spiritually, we become a revelation of a life in Christ even though we may suffer persecution for the way we live:
2 Corinthians 4:10-12: "We always carry around in our body the death of Jesus, so that the life of Jesus may also be revealed in our body. For we who are alive are always being given over to death for Jesus' sake, so that His life may be revealed in our mortal body. So then, death is at work in us, but life is at work in you."
Jesus Himself summed up this "do what is right in the eyes of everybody" when He said in Matthew 5:14-16:
"You are the light of the world. A city on a hill cannot be hidden. Neither do people light a lamp and put it under a bowl. Instead they put it on its stand, and it gives light to everyone in the house. In the same way, let your light shine before men, that they may see your good deeds and praise your Father in heaven."