If you've been wondering why, in these scientifically enlightened times, belief in God, angels and saints is so common and so persistent, Faber goes a long way toward answering your question. His explanation is based on the development of the human infant's brain. I'll condense his explanation into my own words.
An infant's neocortex has billions of `seedling' neurons searching for stimuli which shape the way these neurons grow; the way its brain get `wired'. And the way the neurons grow conditions their response to future stimuli. The infant's initial experiences are with its caregivers (usually its mother). Initially the infant doesn't distinguish between itself and its caregiver; to it they're one omnipotent organism. The nurturing, warmth and comforting it receives in response to its whimpers and cries are seemingly self-induced -- the neurons in its neocortex initially get `wired' so that the infant unconsciously believes it induces it own nurturing.
As the infant grows it learns to distinguish itself from its caregivers. But the early `wiring' is still in its brain available to be re-stimulated eventho' new patterns continue to be laid down along with the initial `wiring'. Until the child reaches its third year, it has no conscious memory (infantile amnesia). But the unconscious memories are still there in its brain available to be re-stimulated. As the child separates itself from its caregivers, it may compensate with an imaginary companion (such as a doll or blanket) that it can turn to for comfort.
If at this age the child is taught about supernatural companions -- its putative Father in Heaven, Baby Jesus, Mother Mary and/or Guardian Angel -- these can re-stimulate its brain's initial `wiring' to unconsciously resonate with the child's infantile desires. It can self-induce its own comforting unbeknown to its conscious mind which believes the projected comforting is coming from a supernatural entity Who seems very real. And thru-out its life, the person can induce comforting by praying to its imagined omnipotent `caregiver'. Faber does a much better job of explaining and documenting all this, so if my description stirs your interest, get Faber's new book. He shows the dire consequences of subjecting children to religious stories.
However what Faber doesn't explain is how some of us managed to escape the influence of our brain's early `wiring' so that we're no longer (or never were) religious. We can't all have had bad mothering so that our infant brain never got thus `wired', and many of us were subjected to early religious indoctrination. Faber briefly raised and answers the question on page 34 ("... other neural connections arise as we mature ...") and on pages 43, 103 ("moving on") and 121. But he alludes to what I believe is a better explanation when he says on page 215 "... the unconscious is working to locate for us sources of attachment and security as we undertake our separate, dangerous journeys through the world." I believe there's a rudimentary Urge to Life in us humans (and in all organisms) which propels growth and maturation to "undertake our journeys in the world." We may sometimes grow weary and seek respite, but a healthy person is in touch with their Life Urge and tries to eschew infantile regression. Even so there's still another hazard that the person disown their Life Urge and instead project it out onto an imagined 'god'. If these ideas intrigue you, take a look at Amazon's detail pages on my book "Concepts: A ProtoTheist Quest for Science-Minded Skeptics."
Nonetheless I highly recommend Faber's book. He helped me better understand why religious beliefs are so common and persistent. Be forewarned tho' - I found myself getting impatient with his writing style. As a professor of English apparently he enjoys finding just the right words and using all of them, saying the same thing several ways. Moreover he's not adverse to long sentences and long paragraphs. And he skillfully strings together series of quotes into well constructed sentences. So rather than get impatient, I slowed down and tried to savor his writing.