Here is the 4 part harmony choral sheet music for The Thrice-Holy Hymn. It is based upon the Byzantine hymn by Lykourgos Petrides and arranged by Chrysanthy D. Therianos of Eikona.  

With the purchase of this PDF, you have the right to copy it for use in your church.  However, any adaptation, arranging and/or transmission of this copyrighted music requires the written consent of the copyright owner, Chrysanthy D. Therianos. Unauthorized uses are infringements of the copyright laws of the United States and other countries and may subject the user to civil and/or criminal penalties.