The Deception of the Unregenerate Heart

Sam Storms' Signs of the Spirit is a good distillation of the wisdom of Jonathan Edwards' spiritual masterpiece, Religious Affections. (Though the subtitle doesn't indicate this, the last third of Sam's book adds a distillation of JE's Personal Narrative [found in this volume], which basically turns from the third person to the first person in JE's writing on true spiritual life, describing his own experience autobiographically.)

This was a good statement from Sam on understanding the human heart--

The unregenerate heart is quite capable of self-deception, self-flattery, and a self-confidence that leads it to heartily assert its safety with God.

True believers embrace the assurance of salvation with humility and caution, whereas the false assert it with a brazen confidence. . . . True believers, unlike hypocrites, are also keenly aware of their own sin and the potential it has for leading them into a false sense of security. It is also the case that Satan will leave a hypocrite in his false assurance (and perhaps even embolden him in it), whereas he may constantly attack the born-again believer lest the power of hope in his heart strengthen his commitment to holiness and purity of life.

--Sam Storms, Signs of the Spirit: An Interpretation of Jonathan Edwards' Religious Affections (Crossway 2007), 70, explaining the eleventh of 12 signs that don't necessarily point one way or another as to authentic spiritual experience