William Law emphasizes that humility is essential for true piety and the foundation of all virtues. He encourages believers to make humility a daily practice, recognizing their own weaknesses and the pervasive nature of pride in their lives. Law asserts that true humility is rooted in a realistic understanding of one's condition and that one must continually strive to learn and grow in humility. He warns against the dangers of pride, which can infiltrate every aspect of life, and stresses the importance of acknowledging one's need for humility as a sign of spiritual growth. Ultimately, he calls for a humble heart that seeks God earnestly and recognizes the ongoing journey of learning humility.