Feeling at ease in Christ is not something that can be taught by book, it can only be learned by experience.
This does not take away the value of assembling together with the saints, or the position of a Pastor as one who teaches and shepherds. Through the Pastor and studying the Word of God we gain intuitively knowledge. The Holy Spirit then takes that knowledge and teaches us how to properly apply it in situations in our lives, whether to another saint or to those outside of the Church.
and let us observe one another unto stimulating love and proper works, not forsaking the assembling of ourselves, just as is the custom of some, but encouraging and the much more as much as we see the day approaching, Hebrews 10:25