If you read Canterbury Tales, you know that I'm a big fan of the Church's traditional practice of eastward oriented cathedrals and churches, as well as the practice of priests celebrating Holy Mass ad orientem or ad Deum.
I also dedicate space in my book The Crucified Rabbi on the importance of the "East" in Scripture and in liturgy from a Jewish and Catholic point of view.
Here's a great quote from Origen regarding the book of Leviticus on the importance of eastward orientation.
"God’s word tells us: The high priest shall put incense on the fire in the
sight of the Lord. The smoke of the incense shall cover the mercy-seat above
the tokens of the covenant, so that he may not die. He shall take some of
the blood of the bull-calf and sprinkle it with his finger over the mercy-
seat toward the east.
"God taught the people of the old covenant how to celebrate the
ritual offered to him in atonement for the sins of men. But you have
come to Christ, the true high priest. Through his blood he has made
God turn to you in mercy and has reconciled you with the Father.
You must not think simply of ordinary blood but you must learn to
recognize instead the blood of the Word. Listen to him as he tells
you: This is my blood, which will be shed for you for the forgiveness of sins.
"There is a deeper meaning in the fact that the high priest sprinkles
the blood toward the east. Atonement comes to you from the east.
From the east comes the one whose name is Dayspring, he who is
mediator between God and men. You are invited then to look always
to the east: it is there that the sun of righteousness rises for you, it
is there that the light is always being born for you. You are never
to walk in darkness; the great and final day is not to enfold you in
darkness. Do not let the night and mist of ignorance steal upon you.
So that you may always enjoy the light of knowledge, keep always in
the daylight of faith, hold fast always to the light of love and peace."
- Origen, Hom. 9, 5. 10: PG 12, 515. 523.
Since the earth is a cosmic temple, the East represents the dawning of light, the rising of the sun, the resurrection of the Son.