1) The (Grounding) Moral Argument
P1) Objective moral facts/duties/values exist.
P2) God is the only possible source of objective moral facts/duties/values. (Alternatively, if objective moral/facts/duties/value exist then God must exist.)
Conclusion: Therefore, God exists (from P1 and P2).
2) The (Epistemological) Moral Argument
P1) If we are to know about morality and our moral duties then God must exist.
P2) We do know about morality and our moral duties.
Conclusion: Therefore, God exists (from P1 and P2).
3) The (Motivational) Moral Argument
P1) If we are ever to be motivated to act morally there must be a God.
P2) We can be motivated to act morally.
Conclusion: Therefore, there must be a God (from P1 and P2).
4) Kant's Moral Argument
P1) We ought to achieve the Summum Bonum (perfect good).
P2) Ought Implies Can.
P3) We can achieve the Summum Bonum (from P1 and P2).
P4) God is a necessary condition for us to achieve the Summum Bonum (because we can't do it without him).
Conclusion: Therefore, God exists (from P3 and P4).