The Doubting Soul's Rest
It is possible for a Christian to develop a lifestyle that induces lethargy of spirit, a melancholic disposition, and low levels of assurance. Some physical conditions have a similar effect on our spirits. All this should be borne in mind. Yet, at the end of the day, there is a promise given to us in Scripture from God himself: “Draw near to God, and he will draw near to you.” [James 4:8] On that word the doubting soul may rest.
Sinclair Ferguson. The Whole Christ (pp. 232-233). Crossway. Kindle Edition.