Philippians 1:12-20

v12-14: Paul's suffering and imprisonment had led to the advance of the gospel. "A strange outworking of Providence is seen here, that such a great good as the advancement of the Gospel could be drawn out of such a great evil as the confinement of the apostle."  It's a reminder that though God's people can be chained, His Word cannot be.

v15-17: Not every preacher of the gospel does so for the right motives. "Let us not think it strange if... there are such people."

v18-20: We can rejoice, even when the gospel is preached by those who do so out of selfish ambition, because when Christ is preached, "it may lead to the good of many people." It is possible that by the grace of God, the preaching of the gospel by them "be made to lead to the salvation of the people" even if those preaching to them are not saved themselves.