The ears of many of our hearers are stopped up with earth! I mean the cares of the world, that the Word preached will not enter, according to that in the parable, ‘Hearing, they hear not’ (Matthew 13:13). We read of Saul, his eyes were open—yet ‘he saw no man’ (Acts 9:8). A strange paradox! And is it not as strange that men’s ears should be open—yet ‘in hearing hear not?’ They mind not what is said: ‘They sit before you as my people—but their heart goes after their covetousness’ (Ezekiel 33:31). Many sit and stare the minister in the face—yet scarcely understand a word he says. They are thinking of their wares and are often casting up accounts in the church. If a man is in a grinding-mill, though you speak ever so loud to him—he does not hear you for the noise of the mill. We preach to men about matters of salvation—but the grinding-mill of worldly business makes such a noise that they cannot hear! ‘In hearing, they hear not.’ It being thus, ministers who are called ‘sons of thunder’ had need often ascend the mount and ‘lift up their voice like a trumpet’ (Isaiah 58:1) that the deaf ear may be cleaned and unstopped, and may hear ‘what the Spirit says unto the churches’ (Revelation 2:7).
As some have earth in their ears—so others have a stone in their hearts! They make ‘their hearts as an adamant stone, lest they should hear’ (Zechariah 7:12). The ministers of Christ therefore must be frequently brandishing the sword of the Spirit and striking at men’s sins, that, if possible, they may at last pierce the heart of stone! When the earth is scorched with the sun, it is so hard and crusted, that one shower of rain will not soften it. There must be shower after shower before it will be either moist or fertile. Such a hardened piece, is the heart of man naturally. It is so stiffened with the scorchings of lust, that there must be ‘precept upon precept’ (Isaiah 28:10). Our doctrine must ‘distill as the dew, as the small rain on the tender herb, and as the showers upon the grass’ (Deuteronomy 32:2).
Thomas Watson, The Beatitudes