Paul and all those who were with him went through difficult times because they were committed to preaching about Jesus. In doing this, they were sharing in the sufferings of Christ. Other people saw their dedication and were drawn to Jesus.
2 Corinthians 4:8-12
8 We are pressed on every side by troubles,
but we are not crushed.
We are perplexed,
but not driven to despair.
9 We are hunted down,
but never abandoned by God.
We get knocked down,
but we are not destroyed.
10 Through suffering, our bodies continue to share in the death of Jesus so that the life of Jesus may also be seen in our bodies.
11 Yes, we live under constant danger of death because we serve Jesus, so that the life of Jesus will be evident in our dying bodies. 12 So we live in the face of death, but this has resulted in eternal life for you.