Laying a good foundation is essential for the full growth of a Christian as well as for the building up of the body of Christ. The apostle Paul exhorted young Timothy to "have an outline of sound words which words thou hast heard of me, in faith and love which are in Christ Jesus. Keep by the Holy Spirit which dwells in us, the good deposit entrusted" (2 Tim 1:13,14 Darby's). Such good deposit of fundamental teachings on practical Christian living forms a sure foundation on which to build. In this fourth book on Basic Lesson Series, messages are given on If Any Man Sin, Apology and Restitution, Restore Your Brother, the Believer's Reaction, Deliverance, Our Life, and the Will of God. May we learn these lessons faithfully.