What is the difference between a Deist and a Theist?
Really, there is no difference. A Deist is one who believes in Deus, the Latin word for God. A Theist is one who believes in Theos, the Greek word for God.
Many people speak of Deism as if it meant Atheism, but this is a mistake. Deism, however, was formerly used to designate one who, though believing in God, denied His revelation in the Scriptures, and was not a Christian. Theism is a word of more modern growth, and is used as the opposite of Atheism. Hence, though etymologically the same, the two words are used in a somewhat different sense, deism being made synonymous with infidelity, and theism with faith in God.