There is a reason jewelers display fine diamonds against the backdrop of black felt under bright light. The jeweler wants his fine diamonds to be irresistible to the potential purchaser.

God’s grace in the salvation of men is like the jeweler and his fine diamonds. When the natural man, aided by the Holy Spirit, perceives the blackness of his sin and is shown the beauty of God’s Son under the light of the Gospel, he will run to the Cross of Christ. That’s irresistible Grace.