“The doctrine of Christ crucified is the grand center of union among true Christians.
Does a man really and sincerely glory in the cross of Christ? That is the grand question. If he does, he is my brother: we are traveling in the same road; we are journeying towards a home where Christ is all, and everything outward in religion will be forgotten.
But if he does not glory in the cross of Christ, I cannot feel comfort about him. Union on outward points only is union only for time: union about the cross is union for eternity. Error on outward points is only a skin-deep disease: error about the cross is disease at the heart. Union about outward points is a mere man-made union: union about the cross of Christ can only be produced by the Holy Spirit.”
— J.C. Ryle, ”Christ Crucified”