The Tiara is the Official Headdress of the Pope.  This Tiara represents the triple power that "Christ conferred on His Apostles and their successors, to teach, to govern, to lead men to holiness, making this power, defined by special ordinances, rights and obligations, the fundamental law of the whole Church," per Pope Pius XII in his great and important Encyclical "On The Mystical Body of the Christ And Our Union In It With Christ."

    Now when a man is crowned Pope in an Official Coronation Ceremony and receives this Tiara, he receives this power from Christ Himself.  This is proof from Heaven that this particular man has been given this power from Christ Himself to rule, to govern, to lead men to holiness, and there can be no question of him being a True Pope.  Receiving this Tiara from the Official Church is proof of this.

    Now if a man gets into this position of the Pope and he is not crowned in an Official Coronation Ceremony (but instead is inaugurated) and does not receive the Tiara, then is this not proof from Christ, Himself, that this man is not His Official Representative on earth and has not been given this triple power to teach, to govern, to lead men to holiness and therefore is a false pope who tries to deceive men by taking this power on himself?

Pope Paul VI was crowned Pope in a Coronation Ceremony in which he received the Tiara and was a True Pope until sometime after he wrote his last Encyclical Letter, "Huamanae Vitae" on July 25, 1968, when he became a different man in his thinking, words and deeds.
John Paul I was not crowned Pope in a Coronation Ceremony and did not receive the Tiara but was inaugurated instead.
John Paul II was not crowned Pope in a Coronation Ceremony and did not receive the Tiara but was inaugurated instead.
Benedict XVI was not crowned Pope in a Coronation Ceremony and did not receive the Tiara but was installed instead.

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