Happy Feast of the Transfiguration to those on the old calendar! Happy birthday, as well, to my sister!
Troparion:
Thou wast transfigured upon the mountain, O Christ our God, showing Thy glory to Thy disciples as far as they were able to sustain. Shine forth also upon us sinners, Thine everlasting light, by the prayers of the Mother of God. O Giver of light, glory to Thee.
Kontakion:
Thou wast transfigured upon the mountain, and Thy disciples beheld Thy glory, O Christ our God, as far as they were able so to do: that when they saw Thee crucified, they might know that Thy suffering was voluntary, and might proclaim unto the world that Thou art truly the Brightness of the Father.