There are two kinds of scandals. One is the Christian scandal where we find doctrines or teachings that could cause bewildernment in people because they are either so contrary to the fallen human nature of man or at least too difficult to understand by the ordinary mind. There is the other kind of scandal which Christ condemned wherewith the lapse, carelessness or disobedience of one soul encourage others to do the same.
Christ worked to prevent the first kind of scandal in His disciples. The disciples were going to see both the humanity and divinity of Christ. This would be filled with contradictions. They must see the paradox in Christ and be able to unite both concepts to understand the true Christ. And so when the apostles were about to witness the passion of Christ, Jesus had to show them His Transfiguration so that the passion may not be a source of scandal as an unseemly conduct of a Divinity. The inability to integrate both the humanity and Divinity of Christ had been the major cause of heresy in the Church, as shown in the case of the notification sent by then Cardinal Ratzinger to Fr. Tissa, a SriLankan priest.
Examples of the second kind of scandal would be the behaviours of certain priests and nuns toward the orthodoxy of the Pope, which is outright schism and, therefore, scandal to others; or the attempt of some women to be ordained to the priesthood… which encourages lapse of faith in some or disobedience in others. This is the scandal Christ condemned with such words as: “It is better for them to tie a mill stone around their neck..”
The purpose of the Transfiguration was to remove the scandal of the cross, (the first kind.) St. Leo the Great in his work “The purpose of the Transfiguration” states: “And so in the presence of those chosen witnesses the lord unveils His glory, and clothes with such splendour the Body which is His in common with all other men that His face shines as the sun and His garments appear white as snow. By this tranfiguration He desired to remove from the hearts of His disciples the scandal of the Cross, and then that the lowliness of his voluntary Passion might not trouble the faith of those to whom He now reveals the perfection of His hidden glory.”
The Body of Christ was given in the passion in exchange for the glory that His followers might see coming.
The cross, therefore, is a symbol of what St. Paul declared: “For I reckon that the sufferings of this time are not worthy to be compared to the glory to come, that shall be revealed in us. …. For you are dead; and your life is hid with Christ in God. When Christ shall appear, who is your life, then you also shall appear with him in glory.”
In the cross we see Christ who died for us on the cross. But at the same time, we see the Transfiguration that we shall share with Him if we die with Him. Thus the cross does not become a sad symbol but a symbol of hope.