But does that mean God is male? Does he have a body? Parents? Children? Wife?
Some believers see the fatherhood imagery as purely metaphorical, pointing to a reality beyond human understanding. Others view it as literally true, a prototype of human potential.
"When we speak of God as father, we are using language that limps," says Monsignor Colin Bircumshaw, vicar general of the Catholic Diocese of Salt Lake City. "Hopefully, we take the best qualities of what we know of a father in human terms someone who gives us life, nurtures us, loves and supports us and apply it to God."
Such qualities, however, are inescapably anthropomorphic terms and inadequate to capture God's essence.
"Philosophically, we believe God is beyond our human experience," Bircumshaw says. "Ultimately, God is mystery."
That hasn't stopped individual believers and whole religions from describing, as best they can, the God they worship.
In the beginning • The Bible says God created humankind in his image male and female.
To Jews, that means God is a father who is profoundly connected to his children.
"We acknowledge God as the Father in Heaven, who has an intrinsic bond with every one of his children," says Rabbi Benny Zippel of Congregation Bais Menachem in Salt Lake City. "That relationship cannot ever be severed, no matter how strongly the human transgression."
When Moses came down from the mountain and found the Israelites worshipping a golden calf, God said he would annihilate them, Zippel recounts. "But Moses tells God this is not the Jewish nation. These are your children, and, as a Father in Heaven, you are going to forgive them for their wrongdoing."
Moses prevails, Zippel notes, and God essentially says, "Yeah, you were right.' "
This biblical account shows a god who can be reasoned with, Zippel says, one who can be persuaded like, well, a dad.
Such a notion would be blasphemy to Muslims, says Imam Muhammed Mehtar, leader at the Khadeeja Islamic Center in West Valley City.
The Quran is clear, he says. God is not a father or any kind of human gender.
"God has no children and no parents," Mehtar says. "He is the one and only. There are none like him. He has been the same from time immemorial and will remain the same through time immemorial."
Even the term "God" implies a possible gender or progeny, the imam says, which is why Muslims prefer "Allah."
Suggesting Allah has something to do with human flesh would limit him, Mehtar says. "If I say God is a father, that gives a human form to him, and that would be a major sin."
Thus, there are no depictions of God in Islamic art, no statues or paintings of a man with a white beard or any other kind of artistic rendering.
"God is something so sacred, you cannot draw it," he says. "It is offensive to some and a type of blasphemy. You cannot create a reality of God."
Knowing God • Baha'is address deity as "Heavenly Father," invoking God as creative, protective, wise, knowing and powerful, explains Jan Saeed, director of spiritual life at Westminster College in Salt Lake City and a Baha'i.
"We don't believe God is male or female, though, but [God] has attributes that humans typically view as masculine or feminine. You could say that God would be like a father kind, caring and loving, who wants to protect his children but mothers are like that, too."
Any descriptions or titles for God ultimately have limitations, but God doesn't, she says. "We think of God as the 'unknowable essence.' "
When Moses wanted to see the divine for himself, she says, God replied, "You can't see me or you will die. You cannot comprehend me."
Followers of Jesus Christ believe they have a way to know God through his son.
"If you know me, you know my father," Jesus says in the New Testament. "I and my father are one."
That's why the Greek Orthodox place an image of Christ in the dome of their churches, says Father Matthew Gilbert of Salt Lake City Holy Trinity Cathedral. "We know the father through the son. It can be the same as knowing your neighbor. It's a spiritual process."
In the Old Testament, God appeared to Abraham and Sarah in the form of three angels, which is why the Orthodox use three angels to depict the Trinity Father, Son and Holy Spirit.
"God wanted to have a relationship with his creation, to heal man and bring him back to where he was meant to be," Gilbert says. "God loves us and takes care of us."
Jehovah's Witnesses believe in the Bible, but not in the Trinity, says Jeffrey Tackett, a Utah representative of the faith. "That teaching is not in the Bible."
Jesus himself is clearly the son of God, Tackett writes in an email, pointing to biblical passages quoting Peter and God himself at Jesus' baptism. "He was created by Jehovah and submissive to him."
Does God have a body? • The Bible refers to the "hand of God," "the finger of God" and "the ear of God." But most believe God is more abstract than literal.
Most, that is, except Mormons.
When Jesus taught his disciples how to pray, the man Christians believe was the world's savior addressed his words to "Abba," says Philip Barlow, Arrington Chair of Mormon History and Culture at Utah State University and himself a Latter-day Saint. In Aramaic, that is seen by some as the most intimate term for father, more like "papa" or "daddy."
LDS Church founder Joseph Smith taught that God has a body of "flesh and bones," Barlow says, and that he is literally the father of mankind.
"It is a potent and radical notion," Barlow says. "Instead of being anthropomorphic, Mormons believe that humans are theomorphic."
Smith's celebration of God's physicality, he says, should lead to increased respect for the material world, especially bodies.
The first time Barlow carried one of his children in a Snugli, a pouchlike carrier for babies, he had a spiritual appreciation for the "physicalness of that little life of which I was the father as much as for the sexual consummation that made the creature in the first place."
"In Mormonism, fatherhood is particularly sacred," he says, "part of the relational nature of salvation and exaltation."
So what happens when human fathers prove difficult or unloving?
"If people have a poor image of a father in terms of their own human experience, this can handicap, in a psychological way, their relationship with God spiritually," says Bircumshaw, the vicar general. "They can take that into their relationship, which can be very damaging."
Tresa Edmunds, a Mormon writer and feminist in Modesto, Calif., says she has talked with women through the years whose concept of a Heavenly Father is tainted by a neglectful or abusive father.
"It colors their whole experience with the divine," Edmunds says. "If your father sexually abuses you and twists the divine role of creation and sexuality, that's how you approach Heavenly Father. It can damage your relationship with the church."
Some LDS women in this situation can no longer pray to Heavenly Father, she says. They turn, instead, toward Mother God.
A divine feminine • If you study the ancient Jewish Kabbalistic scriptures, Zippel says, it is apparent that God has masculine and feminine traits.
The term "Father in Heaven" may be a practical simplification, he says, but God is more like a "Parent in Heaven."
One of the fundamental teachings in Jewish mysticism, Zippel says, is the essential nature of creation, which requires male and female participants.
Mormons, in their literalism, see Heavenly Mother as an essential partner with God the Father, but speak about her rarely and only in vague, reverential tones.
Still, Barlow says, it stands as a compelling doctrine.
"We are made in the image of God, meaning both male and female, and sexual union," he says. "It is not just metaphorical, but an important, literal truth."
Catholics also see God as father and mother.
"The essence of God is love," Bircumshaw says. "You could easily speak of God as mother because we are speaking of the source of life and love. We cannot speak of father in human terms without thinking of the opposite, mother."
It is not about gender, he reiterates, it's about relationship.
Even earthly fathers and mothers can grasp that.