“No less than their biblical counterparts, contemporary preachers are called to be channels of the word of God. The metaphors of herald and ambassador apply as much to them as they did to the apostles. This high view of preaching came to clear expression in the Reformed Second Helvetic Confession of 1566: Praedicatio verbi Dei est verbum Dei (the preaching of the word of God is the word of God).”
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“This high view of preaching can never be the boast of preachers, of course; it can only underscore their responsibility. For with the prophets we noticed that their authority did not reside, ultimately, in their calling or office but in the words they spoke, whether they were from the Lord. So it is with preachers today: they have a word from the Lord, but only if they speak the Lord’s word. The only norm we have for judging whether preachers speak the word of the Lord is the Bible” (Sidney Greidanus, The Modern Preacher and the Ancient Text: Interpreting and Preaching Biblical Literature, 8-9).