Is it possible for a man's consciousness to become like that of a newborn child?

According to Osho, yes: consciousness can return to newborn-like innocence when the mind’s winds of desire and thoughts settle, like a lake becoming clear after storms. Your original purity never disappears; it’s rediscovered by awareness and letting go. The saint is childlike, beyond rules, sin and virtue, sometimes appearing mad or ecstatic, because nothing is fixed inside—only innocence and emptiness.