Samuel Logan Brengle emphasizes the duality of God's nature, highlighting that while He is rich in mercy, He is equally terrible in wrath. The sermon underscores the importance of recognizing the terror of the Lord as a motivator for repentance and a call to holiness, warning that judgment follows wrongdoing just as night follows day. Brengle urges that this truth should be preached earnestly and with reverence, as it reflects the unchangeable holiness of God's character. He contrasts the mockery of sin with the reverential fear that leads believers to seek refuge in God's love and mercy. Ultimately, the sermon calls for a balance of holy fear and love, urging listeners to make their calling sure and endure to the end.