Today is the feast of Theophany.

Troparion - Tone 1

When You, O Lord were baptized
in the Jordan
The worship of the Trinity
was made manifest
For the voice of the Father
bore witness to You
And called You His beloved Son.
And the Spirit, in the form of a dove,
Confirmed the truthfulness of His word.
O Christ, our God, You have revealed Yourself
And have enlightened the world, glory to You!

Kontakion - Tone 4

Today You have shown forth to the world, O Lord,
and the light of Your countenance has been marked on us.
Knowing You, we sing Your praises.
You have come and revealed Yourself,
O unapproachable Light.

From the Royal Hours of Theophany

Read about the prayers of the Hours and about the Royal Hours at OrthodoxPhotos. 

The waters saw You, O God, the waters saw You and were afraid.

~ Prokeimenon of the Prophecy for the Sixth Hour 

Why do you stop the flow of your waters, O Jordan?
Why do you make your streams flow back?
Why do you not follow your natural course?
“I cannot bear the fire which consumes me,” it said.
“I am amazed and shudder at the extreme condescension.
I have not learned to wash the pure or cleanse the sinless.
I have learned only to wash the filthy garment.
Now Christ, Who is baptized in me,
teaches me to burn the thorns of sin.
And John, the voice of the Word, bears witness with me.
He cries out: “Behold the Lamb of God,
Who takes away the sin of the world.”
Let us the faithful cry to Him:
“O God, Who shone forth for our salvation, glory to You.”

~ Stikheron for the Sixth Hour, Tone 5

With your hand, O Baptist,
you touched the pure head of the Master.
With your hand and your finger you showed him to us.
Stretch out this hand toward Him on our behalf,
since you have great boldness;
for He witnessed to you as greater than all the prophets.
And again, with your eyes, O Baptist,
you saw the Holy Spirit descend in the form of a dove.
Lift your eyes to him and make him gracious toward us.
And come and stand with us.
Come and stand with us.
Come and stand with us.
Confirm our song and lead our feast.

~ Stikheron for the Ninth Hour, Tone 5 

Not One Theophany, but Two 

We shall now say something about the present feast. Many celebrate the feastdays and know their designations, but the cause for which they were established they know not. Thus concerning this, that the present feast is called Theophany — everyone knows; but what this is — Theophany, and whether it be one thing or another, they know not. And this is shameful — every year to celebrate the feastday and not know its reason.

First of all therefore, it is necessary to say that there is not one Theophany, but two: the one actual, which already has occurred, and the second in future, which will happen with glory at the end of the world. About this one and about the other you will hear today from Paul, who in conversing with Titus, speaks thus about the present: “The grace of God hath revealed itself, having saved all mankind, decreeing, that we reject iniquity and worldly desires, and dwell in the present age in prudence and in righteousness and piety” — and about the future: “awaiting the blessed hope and glorious appearance of our great God and Saviour Jesus Christ” (Tit 2:11-13). 

~St. John Chrysostom, Sermon on Theophany