"Christianity and Liberalism" is a book by J. Gresham Machen published in 1923. In it, Machen argues that Christianity and liberal theology are fundamentally incompatible. He critiques the liberal movement within Christianity, which seeks to adapt religious beliefs to modern scientific and philosophical ideas, suggesting that this approach undermines core Christian doctrines. Machen emphasizes the importance of maintaining traditional beliefs, such as the divinity of Jesus Christ and the authority of the Bible. He believes that true Christianity should remain distinct from liberal ideologies, which he views as a departure from authentic faith.