A Quaker author whose notable work Celebration of Discipline served as a foundational influence for renewed interest in spiritual disciplines within evangelical circles. His categorization and introduction of spiritual practices set a precedent that influenced Whitney's approach, despite some theological concerns within evangelical communities.

A professor and author whose philosophical rigor and theological insights significantly impacted Whitney's thought on spiritual growth. Willard emphasized contemplative practices and provided an intellectual framework for understanding the role of spiritual disciplines in holistic transformation.

A historic movement emphasizing disciplined piety and spiritual practices as means of holiness and communion with God. Their theological legacy and writings, particularly those of John Owen and Richard Baxter, heavily influenced Whitney’s framework for spiritual disciplines.