The early church hammered out creeds that set the boundaries of Christology and the doctrine of the Trinity. But they did an inadequate job with God the Father.
What do the Creeds state about the Father?
His consubstantiality with the Son; the Spirit’s procession from Him; and his reigning with the Son at His right hand until the judgment. But these points are really about the Son or Spirit.
The only thing the creeds say about the Father in His own right is that he is the “maker of heaven and earth, of all things visible and invisible.”
But even Deists believe that.
Some things that could be affirmed about the Father:
1. That He is good, and made the creation good. This cuts off Gnosticism at the root.
2. That He, with the Son and Spirit, is the YHWH of the Old Testament, and the God of Israel. This eliminates Marcionism, Arianism, and the theologies of Jehovah’s Witnesses and Mormons.
3. That He is merciful and loves to forgive sins. This would rule out tendencies to talk about the Son as loving and merciful, and make the Father into a sort of harsh and strict tyrant. I have heard evangelicals talk as though the Son saves us from the Father, so that the Father’s role in salvation is to bring the wrath from which the Son saves us. It’s hard to say “Abba, Father” to a God like that.
4. That He is a person. He is not a principle or a force.
5. That He loves men and enters into covenant with them.
6. That He is manifested in Jesus, so that we can understand His character from the character of Jesus.
Here’s my crack at it:
“I believe in God the Father Almighty, the Maker of Heaven and Earth, the Father of lights from whom every good and perfect gift proceeds, the God of Abraham, Isaac, and Jacob; whose mercy is from everlasting to everlasting, who so loved the world that He gave His only begotten Son, for whom He sanctifies the Church to be a bride, so that He might be our Father and that we might live with Him.”