In Leviticus we are introduced to one of the most important themes of the Bible: the Lord is a holy God who calls His people to be holy. The Hebrews writer tells us that without holiness, no one will see the Lord (Hebrews 12:14). John Wesley considered that challenging statement as perhaps the most unpopular verse to preach on in the entire New Testament. In this lesson we consider God’s holiness, the practical meaning of the term ‘holy’, popular attempts to evade this teaching, and special challenges facing those who seek to live holy lives.