elaudit et apefit

Corruption of "claudit et aperit," a transposition of the words in the Advent antiphon "O Clavis David"

Coat of Arms of Archbishop John Hughes

the first archbishop of New York

who in 1858 began building this Cathedral

Facade of Saint Patrick's Cathedral, New York

N.B. the fleur de lis on one of the keys (an image of Our Lady)

the keys themselves referring to the keys of Peter

the absolute nature of Papal infallibility

and the episcopal authority in general
as given by Christ Himself
Clavis David!

"He closed and he opened" [with the key of David].

O Clavis David

O Clavis David, et sceptrum domus Israel;qui aperis, et nemo claudit;claudis, et nemo aperit:veni, et educ vinctum de domo carceris,sedentem in tenebris, et umbra mortis.

O Key of David and sceptre of the House of Israel;you open and no one can shut;you shut and no one can open:Come and lead the prisoners from the prison house,those who dwell in darkness and the shadow of death.

In a ceremony at Old St. Patrick’s Cathedral, Archbishop Hughes proposed “for the glory of Almighty God, for the honor of the Blessed and Immaculate Virgin, for the exaltation of Holy Mother Church, for the dignity of our ancient and glorious Catholic name, to erect a Cathedral in the City of New York that may be worthy of our increasing numbers, intelligence, and wealth as a religious community, and at all events, worthy as a public architectural monument, of the present and prospective crowns of this metropolis of the American continent.” 

http://saintpatrickscathedral.org/history-heritage

P.S. If in New York go to Saint Patrick's Cathedral which has been completely cleaned and restored. It's the best it has looked in over a hundred years! The facade picture above is from before the cleaning!