Jesus is the greatest missionary who ever lived or will ever live. In fact, Jesus' incarnation was in many ways a mission trip led and empowered by God the Holy Spirit.
First, Jesus came into a sinful culture. As a missionary, Jesus left the culture of heaven to come into a sinful culture on the earth. This cross-cultural transition was starker than any missionary has ever experienced. Jesus came from the culture of heaven, where there was no temptation, sin, sinners, or death. In entering into culture on earth, Jesus was tempted by Satan to sin, surrounded by sinners, and both witnessed and experienced death as the penalty for sin.
Second, Jesus learned firsthand about a sinful culture. As the perfect missionary, Jesus did not learn about the sinful culture from a careful and safe distance. No, Jesus built friendships with sinners, Jesus learned the language of sinners, Jesus ate food with sinners, Jesus drank wine with sinners, and Jesus participated in the parties and holidays of sinners. The religious types in Jesus' day were incensed by his participation in sinful culture with sinners, and Jesus himself reports that when they saw him they would rebuke and mock him, saying, "Look at him! A glutton and a drunkard, a friend of tax collectors and sinners."
Third, Jesus did not condone sin, nor did he sin, himself. Jesus said that he never sinned. Furthermore, the Bible elsewhere emphatically declares that Jesus is the only person who has never sinned. While Jesus never broke any of God's laws as revealed in Scripture, he did not hold certain social and religious customs (those that do not find their authority in Scripture) in high regard. Subsequently, Jesus frequently broke various social and religious customs when he felt it was necessary to further the work of God. Examples include healing on the Sabbath, throwing tables over in the temple, eating with godless sinners, and not washing his hands before eating.
Mark Driscoll & Gerry Breshears, Vintage Church