God the Father is a title given to God in various religions, most prominently in Christianity. In mainstream trinitarian Christianity, God the Father is regarded as the first person of the Trinity, followed by the second person God the Son (Jesus Christ) and the third person God the Holy Spirit. Since the second century, Christian creeds included affirmation of belief in "God the Father (Almighty)", primarily as his capacity as "Father and creator of the universe". Yet, in Christianity the concept of God as the father of Jesus Christ goes metaphysically further than the concept of God as the Creator and father of all people, as indicated in the Apostle's Creed where the expression of belief in the "Father almighty, creator of heaven and earth" is immediately, but separately followed by in "Jesus Christ, his only Son, our Lord", thus expressing both senses of fatherhood.
Although similarities exist among religions, the common language and the shared concepts about God and his title Father among the Abrahamic religions is quite limited, and each religion has very specific belief structures and religious nomenclature with respect to the subject. While a religious teacher in one faith may be able to explain the concepts to his own audience with ease, significant barriers remain in communicating those concepts across religious boundaries.
In Christianity, God is addressed as the Father, in part because of his active interest in human affairs, in the way that a father would take an interest in his children who are dependent on him and as a father, he will respond to humanity, his children, acting in their best interests. Many believe they can communicate with God and come closer to him through prayer – a key element of achieving communion with God.
In general, the title Father (capitalized) signifies God's role as the life-giver, the authority, and powerful protector, often viewed as immense, omnipotent, omniscient, omnipresent with infinite power and charity that goes beyond human understanding. For instance, after completing his monumental work Summa Theologica, Catholic St. Thomas Aquinas concluded that he had not yet begun to understand ‘God the Father’. Although the term "Father" implies masculine characteristics, God is usually defined as having the form of a spirit without any human biological gender, e.g. the Catechism of the Catholic Church #239 specifically states that "God is neither man nor woman: he is God". Although God is never directly addressed as "Mother", at times motherly attributes may be interpreted in Old Testament references such as Isa 42:14, Isa 49:14–15 or Isa 66:12–13.