What is the harm in not believing in God's existence ?

Swami Sivananda, "If we have no faith in God, we will be born again in this world and will undergo considerable miseries. The ignorant, faithless doubting self goes to destruction. He cannot enjoy the least happiness. Neither this world nor that beyond is there for the doubting self. Those who have no faith in God do not know what is right and what is wrong. They have lost the power of discrimination. They are untruthful, proud and egoistic. They are given to excessive greed, wrath and lust. They hoard up money by unlawful means. They become men of demoniacal nature. They commit various sorts of atrocious crimes. They have no ideals for their lives. They are thrown into demoniacal wombs. They sink into the lowest depths, deluded birth after birth.

"Some one hundred and fifty years ago there lived a very famous Yogi-jnani (a self-realized saint) by name Sadasiva Brahmendra Sarasvati in Nerur, near Karur, in the district of Tiruchirapalli in South India. He is the author of Brahma Sutra Vritti and Atma Vidya Vidalasa and various other books. He has done innumerable miracles. Once when he was absorbed in Samadhi (superconscious state) on the banks of the Cauvery, he was carried away by the flood and thrown somewhere else. He was deeply buried underneath the sand. Labourers went to plough the fields. They hit against the head of the Yogi and some blood oozed out. They dug out, and to their astonishment, they found a Yogi seated in Samadhi.

"On another occasion, as an Avadhuta, Sadasiva Brahmendra entered the Zenana (tent) of a Mohammedan chief naked. The chief was quite enraged at the sage. He cut off one of the arms of the Mahatma (saint). Sadasiva Brahman walked away without uttering a word and without showing any sign of pain. The chief was greatly astonished at this strange condition of the sage. He thought that this man must be a Mahatma, a superhuman being. He repented much and followed the sage to apologize. Sadasiva never knew that his arm was cut off. When the chief narrated to the sage what had happened in the camp, Sadasiva excused the chief and simply touched his maimed arm. Sadasiva Brahman had a fresh arm. It is the life of this sage that made a very deep impression in my mind. I came to a very definite conclusion that there is a sublime divine life independent of objects and the play of the mind and the sense. The sage was quite unconscious of the world.

"He did not feel a bit when his arm was cut off. He ought to have been absorbed in the Divine Consciousness, he ought to have been one with the Divine. Ordinary people yell out when there is even a pin-prick in their bodies. When I heard of the marvellous incident in the life of Sage Sadasiva from Apta (realized) persons and when I read in the book, it gave me a very strong conviction about the Divine Existence and a divine eternal life where all sorrows melt, where all desires are satisfied and one gets supreme bliss, supreme peace and supreme knowledge."

An excerpt from "May I Answer That?"