According to Christian belief, a being or power which creates and sustains everything, and to which all living things return upon dissolution.
The Royal arms of the United Kingdom as borne in England: Dieu et mon droit (The word of God is law; see image below).
The preamble of Germany's constitution:
"Conscious of their responsibility before God and men, animated by the resolve to serve world peace as an equal partner in a united Europe, the German people have adopted, by virtue of their constituent power, this basic law."
The preamble of the Canadian Constitution Act, 1982 (which, ironically, also identifies and purports to protect "freedom of religion" as a "fundamental freedom" (at §2):
"Whereas Canada is founded upon principles that recognize the supremacy of God and the rule of law."
God was raised in US v Macintosh where, at page 633, Justice Hughes wrote:
"The essence of religion is belief in a relation to God involving duties superior to those arising from any human relation."
In US v Seeger, the judges of the Supreme Court of the United States agonized over the word God and, amongst many other references, one borrowed from Buddhism:
"Each one of us is but a cell, as it were, in the body of the Great Self."
In Cameron, the testatrix concluded her will with the words the whole of my estate must be used for God only."
The lower Court took it as a valid disposition by reading it to mean "used for religious purposes".
But on appeal, the Supreme Court disagreed and held that:
"... the trust is so vague and uncertain that the bequest was void and falls into the residue".