Instruct: Classify Amazon reviews into positive or negative sentiment
Query: A Powerful Message That Can Be Understood By All

The Mark of the Christian was written almost 40 years ago and has less than 40 pages. Despite the thinness of his book, Pastor Schaeffer presents a critical message that many people who profess to be Christians need to hear. As stated in John 13:33-35, love must be the distinguishing mark of all Christians. He who fails to love has not been truly changed by the gospel message.