Concerned with the mess left behind by chewing tobacco and smoking pipes, Joseph Smith asked the Lord about the problem. He was given the revelation found in Doctrine & Covenants 89, which we now call the Word of Wisdom. In it, the Lord warns against drinking strong drinks (alcohol), drinking hot drinks (like coffee and tea), and using tobacco. The Lord encourages us to use and eat wholesome herbs, fruits, and grains and to eat meat sparingly. If we keep these commandments, we are promised blessings, including health, energy, wisdom, and knowledge. 

In Doctrine & Covenants 90-92, the Lord gives specific instructions to several Church members to set the Church in order and walk uprightly before the Lord, avoiding pride, slothfulness, and uncleanness.