Titus 1:1-3 (ESV)
Paul, a servant of God and an apostle of Jesus Christ, for the sake of the faith of God's elect and their knowledge of the truth, which accords with godliness,  in hope of eternal life, which God, who never lies, promised before the ages began  and at the proper time manifested in his word through the preaching with which I have been entrusted by the command of God our Savior;
Paul, as always, introduces himself here at the beginning of his letter, and lets everyone know not only who he is but what he is about. He is a servant (a slave) of God, and an apostle of Jesus Christ, he is called on behalf to the elect and their knowledge of the truth. That is he is to instruct them in the truth that accords with godliness, to strengthen their hope of eternal life (faith) which God who never lies, promised before the ages began, not this eternal life is manifested in the preaching with which Paul has been entrusted. This is peculiar. The eternal life that God promises is manifested in his word, through the preaching with which Paul has been entrusted.
How does preaching manifest eternal life? Doesn’t that have to be earned? Isn’t preaching about telling people what they are to do to attain eternal life? In a word, no. Eternal life is given through faith, and faith comes through hearing (Romans 10.) When Paul preaches the Gospel, people hear, believe, and are saved. So god command Paul to preach. The Gospel is communicated through words, not deeds. People can see you being an upright citizen who takes the trash out every Wednesday, mows the lawn faithfully, loves and cares for his family, etc. They will never thereby hear that there sins are forgiven on account of Christ’s death and resurrection on the cross. That is the gospel, and it has to be spoken, communicated in word, so that others might hear, believe, and be saved.