Reason of writing the epistle
Having been informed of your godly love, so well-ordered, I rejoiced greatly, and determined to commune with you in the faith of Jesus Christ. For as one who has been thought worthy of the most honourable of all names, in those bonds which I bear about, I commend the Churches, in which I pray for a union both of the flesh and spirit of Jesus Christ, the constant source of our life, and of faith and love, to which nothing is to be preferred, but especially of Jesus and the Father, in whom, if we endure all the assaults of the prince of this world, and escape them, we shall enjoy God.
Source: Epistle to the Magnesians (New Advent)