If I tell the truth, why do you not believe me? Whoever is of God hears the words of God. The reason why you do not hear them is that you are not of God. (John 8:46-47 ESV)
This is a particularly severe judgment upon all those who despise God’s Word; everyone ought therefore be on guard against this sin and avoid it. But what happens? Despising the Word is such a prevalent evil everywhere in the world that no sin is more commonplace. God’s Word nowadays is despised by people in high and low places, in the secular and spiritual realms; peasant and burgher do not want to listen to it, and they run amok like wild beasts. We preach to them as best we can, but they don’t want to listen. Hence they are of the devil, and he will reward them, as he did the Jews and other scornful persons.
But listen to how the Jews answered Christ, the Lord, over this judgment, “Are we not right in saying that you are a Samaritan and have a demon?” (John 8:48 ESV) In other words, Underneath you’re nothing but a mischievous rogue and a heathen; you are a deceiver and an apostle of the devil, because you do not teach correctly. It’s the same response we get at the hands of smart alecky peasants and burghers today when we reproach them for their shameful scorning of God’s Word. They begin to mock and say, You clowns ought to preach the gospel but instead you only want to scold us; you don’t teach as Christ’s apostles but like the devil himself. This is what we have to listen to. Yet why should we lament? This is what Christ himself experienced at the hands of his people, as he details at length in this Gospel lesson how they slandered him when, to the glory and praise of God alone, he preached for the sake of the people’s spiritual well-being. We can’t expect anything different.
– Martin Luther, Second House Postil for the Fifth Sunday in Lent (John 8:46-59)