Entry of God for Hodder’s The Essentials of Philosophy and Ethics (2016), Martin Cohen ed.
I define God as the supreme idea, concept or entity that regulates ethics.

Philosophers have described the nature of God as the Creator, the Generator, the Principle, the Infinite, the Good, the Being, the One, the Perfect, the Absolute or the Transcendent. The history of these definitions have made God the common ground amongst theology, metaphysics, ontology, ethics and existentialism, for, as Kierkegaard pointed out, any question about God is a question about existence. The Pentateuch already speaks of a God, that is, an ontological statement that coincides with the mysterious definition of an eternal Being by Parmenides. Centuries before Kant, Saint Anselm understood that any intellectual discussion on God is a-posteriori to his Idea, an intuition that studies of isolated non-Western societies have corroborated .
God is a concept as malleable as the history of mankind. Before the Mesopotamian distinction between good and evil was established, primitive cultures associated God to the creative and destructive forces of nature, a conception that was anthropomorphized by the Assyrians , and that the soldiers of Hernán Cortés discovered as late as the 16th-century in their conquest of the Aztec Empire. Plato, under the influence of the Indian philosophers, referred to the supreme God as the Demiurge, that's to say, as the maker and ruler. Aristotle rather understood it as his alter ego, an immobile motor who ponders eternally about himself.

As early as the 5th century BC Xenophanes argued for the ethical nature of God, far more compelling than the capricious behavior of the anthropomorphic gods of Ethiopia, Egypt and Thrace. In the same vein Socrates disdained polytheism and worshipped a single God, an attitude that eventually contributed to his forced suicide. And indeed, Christianity was born as an Ethics, rather than as religion. In the Sermon on the Mount Jesus does not bless a race or a group of believers, but instead those who he calls the poor of spirit, the meek, the merciful, the peacemakers, the persecuted, the righteous and the mournful.
Moses and the prophets of Israel had already associated the concept of justice to God, but, as Plato proved it, 'justice' can be a word as imprecise as 'God'. Jesus objected to the lex talion stated in Exodus and Deuteronomy ('An eye for an eye, and a tooth for a tooth'), and demanded love and forgiveness in the face of violence and oppression. Jesus, nonetheless, abstains himself from formulating e love as mere compassion - as Buddha did. Persuaded that self-sacrifice was the only solution to a continuous circle of retribution, he set up a precedent of his teachings in his own trial, crucifixion and death. As late as 1953, secular spectators could hear the lament of one of Samuel Beckett's characters: 'All my life I've compared myself to him' .

The first Christian writers - Saint John in particular, presented Jesus not only as the Christ, but also as the incarnated God whose main attribute was love. Centuries later the mystic and shoemaker Jacob Boehme would go even further, declaring love to be more important than God, a statement that coincides with Feuerbach's remark that Christianity must sacrifice God as God has sacrificed himself out of love. The cult of Virgin Mary responds to the Christian appraisal of motherhood as the highest manifestation of love, a veneration that has raised eyebrows amongst purists since the Iconoclastic upheaval, and that prompts post-modern Feminist scholars to debate in a neo-Byzantine spirit the true gender of God.
But the definition of God as selfless love conflicts with the morals of the Realpolitik, and the concept of God has been ably adapted to the needs of the world by popes, priests and theologians. The intolerant God of 16-th century Spain has more in common with the stern God of the Roman Emperors than with the cosmopolitan God of the renaissance popes. Under the shadow of an optimistic industrial revolution, the 19th century death of God was also the death of ethics. Two world wars and the raise of Muslim fundamentalism have demonstrated that secular governments cannot underestimate the new conceptualizations of God. Whereas the existential horizon of physics and sciences is death, the teleological nature of any secular or religious ideology inspires believers to accomplish deeds beyond their capacities and even against their own instinct of survival. Thus the God of the Old Testament encouraged a community of runaway slaves to build an empire in Canaan, a deed emulated by the first followers of Mahomet and the 17th century American Pioneers.

In one of his epigrams, Goethe wrote that those who have art and science have religion, whereas those who don't have art and science should have religion. In the same vein Carl Jung understood that religion supplies to common folk what educated men receive from art and philosophy. The sudden discredit of the Scriptures, which until the raise of communism had been the ethical reference of millions of workers and peasants, left an ethical gap that was fulfilled with the writings of Lenin, Mao and Hitler, demagogues who clearly understood that the main function of religion was not metaphysical but moral, and who organized their ideologies as creeds. Days before committing suicide a delirious Hitler prophesied the coming of another Führer. After Lenin's death Stalin presented himself as the Messiah, announced by Marx the Father under the guidance of Lenin's writing - his Holy Ghost.
And many sceptics and reformers have played a role in the history of religion. Recently, the confessed atheist Luis Buñuel questioned through his films the nature of God in a universe ruled by interests and passions, while displaying the heroism of sainthood in a selfish world. Meanwhile, the apparently 'objective' accounts of the Mass Media have made scientists the new priests of our time. 'Science' and 'reason' have become the voice of God. Not surprisingly we hear a new theory of the origin of the universe every year, as provisional and improbable as the arduous speculations of the long-forgotten pre-Socratic metaphysicians.
Essay of God's Definition