At the close of our text we read: “And he,” that is, Christ,” taught daily in the temple. But the chief priests and the scribes and the chief of the people sought to destroy him.” V. 47. After they had become blind to that which belonged to their peace, after they had lost all fear of God’s judgment, they fell from this sin into another without considering it sin; the most bitter enmity grew from their contempt of Christ, until finally they plotted to murder him, the Innocent, and did not rest until their bloodthirstiness was appeased by seeing Christ on the cross.
In their example you see the condition of a person who is hardened. He has fallen so far that he no longer knows what belongs to his peace. In vain God’s Word is preached to him; he no longer knows what belongs to his peace. His heart is hard as a rock. Though the Gospel with all its strength and comfort is preached to him, though Christ is presented ever so movingly in his love of sinners, and though he is in an ever so friendly and urgent a manner incited and enticed, it does not move the hardened person. And though the Law is preached to him in all its threatening severity, though God is described in his frightening righteousness and holiness, and though he is ever so earnestly admonished and warned, it does not move the hardened person. Though grace or wrath, life or death, blessing or curse, heaven or hell, salvation or damnation is presented to him, it is all the same to the hardened person…
…as little as God’s Word enlightens, awakens, and moves a hardened person to repent, so little do also the events of his life, which God permits him to experience. If all goes well, he does not let his heart become soft; the more love God shows him, the more secure, proud, and impudent he becomes, the more he believes that he is in no trouble. On the other hand, if things do not go well, he absolutely refuses to let himself be humbled. Then he murmurs against the Ruler of his fate, and insolently reviles the Almighty in heaven.
Finally, he comes to the point where he no longer feels any sin. His conscience is branded; it no longer carries out its duty; it no longer accuses him; it has become silent. He does only what he wishes without fearing God’s punishment; he becomes a declared enemy of Christ, his work, his Christians, and finally even persecutes them. The tears of anxious parents, brothers, sisters, former fellow-believers, and friends are in vain; the hardened laughs at those who sympathize with him and thus he hurries to meet the day of the revelation of God’s righteous judgment, hell and damnation.
C. F. W. Walther, “Sermon on the Gospel for the Tenth Sunday after Trinity”