Long ago, at many times and in many ways, God spoke to our fathers by the prophets, 2 but in these last days he has spoken to us by his Son, whom he appointed the heir of all things, through whom also he created the world. 3 He is the radiance of the glory of God and the exact imprint of his nature, and he upholds the universe by the word of his power. After making purification for sins, he sat down at the right hand of the Majesty on high, 4 having become as much superior to angels as the name he has inherited is more excellent than theirs.~~Hebrews 1:1-4 (ESV)Notice that this short passage describes God's message as Christ's deity, His atoning death for humanity's sins and His resurrection. Through Jesus, God communicated the hopelessness of pleasing Him through human effort and the glorious hope of His forgiveness because Jesus shed His sinless blood in order to appease God's holy wrath. God showed His acceptance of Jesus' sacrifice by raising Him from the dead and (according to John 3:16) applies the benefits of Christ's work to those who believe in Jesus. We call this narrative "the Gospel message."
This Gospel message assuredly affects how believers live. We realize, first of all, that the Lord purchased our pardon at the very high price of His own blood (1 Corinthians 6:19-20). Through His Holy Spirit, He enables believers to live in obedience to God's righteous standards (Romans 8:1-8, Galatians 5:16). But our obedience, as essential as it is for Christians, merely provides evidence that we have believed the Gospel and have consequently experienced the Holy Spirit's transforming power.
The very fact that changes in our behavior results from the Holy Spirit's power (in contrast to our own efforts) makes the idea that we can "be the message" absolutely ridiculous. Wasn't our innate inability to be what God calls us to be the entire reason for Christ's crucifixion and resurrection in the first place? He has to be God's Word precisely because we can't.