We Believe in God the Father

I believe in one God, the Father...

(Symbol of Faith)

O Master, the One-Who-Is, Lord God, Father Almighty...

(Anaphora of the Liturgy of Saint Basil the Great)

74. Basing  itself  on  Divine  Revelation  and  its  interpretation  by  the  Holy  Fathers,  in  the  Niceno-Constantinopolitan  Symbol  of  Faith the  Church  of  Christ  professes  her  faith  in  God  the  Father  as  follows:  “I believe in one God, the Father, the Almighty, maker of heaven and earth, of all that is seen and unseen.” The fatherhood of God is understood to mean that the Father eternally begets the Son; and that the Holy Spirit proceeds from the Father (See Gregory of Nyssa, Against Eunomius, I, 32). God has created everything and governs all things.  The  Father  is  the  Creator  and  Pantocrator for  all  his  creation.  The universe came into existence because God the Father willed it. We believe in the one God, because there is only one God the Father.1. God the Father Revealed in the Holy Scriptures
75. God reveals himself as Person: “I am who I am,” or “the One-Who-Is”  (Ex 3:14). This God-who-is-Person is the only one who really is.  Everything else exists only inasmuch as God wills it to exist. God is holy, that is, totally different from all creation. There is no other like God. He is unique. Thus, it is not possible to imagine him with our thoughts, or to portray him in any material way: “You shall not make for yourself an idol” (Ex 20:4). In contrast to lifeless idols, the true God lives. Lacking appropriate words to express the mystery of God’s life, Holy Scripture often makes use of anthropomorphisms, thereby applying to God the behavioural traits of a living human being: God loves, converses, assists, pities, is sad, becomes angry, does battle, punishes...
76. In the Old Testament, God reveals himself through various images and events that witness to his presence: in the three travellers whom Abraham  received;  in  the  vision  of  the  ladder  joining  heaven  and  earth  in  the  dream  of  the  patriarch  Jacob;  before  Moses  in  the  burning  bush  that was not consumed; in the pillars of fire and cloud (see Ex 13:21); over the Ark of the Covenant (see Ex 25:22); and as a quiet and gentle breeze (see 1 Kgs 19:12).
77. The Chosen People of God profess their God, exalting him with various names: Saviour (2 Sm 22:2-3; Ps 106[107]:21; Is 43:3-4; Is 45:15); Creator  (  Job 4:17; Job 32:22; Ps 95[96]:6; Is 17:7; Is 51:13); Lord (Ex 3:15); Father (Ps 89[90]:27; Is 9:5; Is 63:16; Mal 1:6); Bridegroom (Hos 2:22); and  Shepherd  (Ps  23[24]:1).  However,  the  Old  Testament  titles  were  merely  prefigurements  of  the  Revelation  of  God  as  the  Father  of  the  only-begotten Son. “No one has ever seen God. It is God the only Son, who is close to the Father’s heart, who has made him known” ( Jn 1:18).
78. The Son of God, Jesus Christ, in whom along with a human nature “the whole fullness of deity dwells bodily” (Col 2:9), reveals the Father: “All things have been handed over to me by my Father; and no one knows the Son except the Father, and no one knows the Father except the Son and anyone to whom the Son chooses to reveal him” (Mt 11:27). Jesus teaches us to address God as “Our Father” (Mt 6:9) and to imitate his perfection:  “Be  perfect,  therefore,  as  your  heavenly  Father  is  perfect”  (Mt 5:48). In Jesus Christ, the invisible God becomes visible for people: “The Father and I are one” ( Jn 10:30) and “whoever has seen me has seen the Father” ( Jn 14:9).

From Christ Our Pascha, 

the Catechism of the Ukrainian Catholic Church