Paul appeals to “conscience” (con = with; science = knowledge) the sense of right and wrong that God put within each person. While some may debate particulars of exactly “what” is right and wrong, we cannot miss the fact that the debate itself proves we have a concept of “right” and “wrong.” Paul’s confidence in the face of misunderstanding is that He knows how God sees His heart. His joy lies in the fact that God’s got his six!
He says, “we [act in a rejoicing manner] because of the way we conduct ourselves in the world”
We too can have a clear conscience in the way we minister in a world of disguises and fakes--we are opposite of the world; therefore we first conduct ourselves in the world with simplicity, honesty; that is, of “one purpose” that is not self-serving. Our Commission from Jesus is to go into all the world with the gospel. We have no hidden agenda. As Jesus calls people out of the kingdom of darkness and into His marvellous light, He builds His church into a living body, a fellowship so we can boast in the fact that we’re not doing ministry for money or fame but out of obedience to Lord Jesus Christ. This is a good reason to give away money because the world perceives the church as takers, not givers.
We conduct ourselves in the world in godly sincerity. What does he mean by “godly sincerity?” There are two approaches to understanding what Paul means here: “sin-cere” means “without wax” (Latin). This is a plausible explanation, but Paul wrote in Greek, not Latin. The word Paul uses here is found only 3x in all scripture, and each occurrence in found in Corinthians (1 Cor 5:8; 2 Cor 1:12 and 2:17). Literally the word means, “on the breathing.” Paul communicates that we conduct ourselves the way God intends, by the Holy Spirit and in truth. When we go into all the world with godly sincerity our gospel is pure, uncorrupt. There No lies in our teaching, unmixed but God-sent.
Finally, we conduct ourselves in the world not with fleshly wisdom. Paul says, “we did not plan this.” Our ministry is God’s doing--any sane person knows you can’t make this stuff up! Remember Paul’s story: his plan was to kill! The implication from Paul is, “hey, if I were working according to fleshly wisdom, we would not be having this conversation and you would be dead at my hand!” Rather, we conduct ourselves in the world by [in] the grace of God. This is the vehicle that moved us around. It is God’s grace that brings salvation to all men.