We are called to preach and are commissioned by God to be a herald. A herald is one who stands in the presence of God to first receive the message before delivering to others. This call to preach comes from God himself. We have to be sure of our calling because only a deep sense of conviction will sustain us through difficult times of discouragement, difficulties, and even depression (see Amos 7:14, 15; Jer. 1:6, 9). It is essential that we know what we have been called to do. Peter tells us that we should “speak as one who utters God’s oracles” (1 Pet. 4:11).