"We may sometimes commit sins while we think we are living in the truth. Then, we will have difficulties and some kinds of uncomfortable feelings in us. It is because the Holy Spirit is groaning in us for He has to dwell in filth." Corinth at the time of Paul was a busy city with many people from various cultures and diverse ethnic backgrounds. There were definitive social classes and the population worshipped a number of different gods. There was also a great deal of moral corruption. Living under such conditions, the believers in the church of Corinth had many conflicts and problems. Furthermore, since the church was newly established, they had difficulties in leading a life in faith. To help them lead a mature Christian life, the apostle Paul gave them biblical answers to many such questions and problems. In today's complex society it is important that we carefully learn and understand its content. This book explains how to understand and practice the matters related with strife, evangelism, marriage, idolatry, and the spiritual gifts.