Edwards describes how emotion and intellect both play a role, but "converting grace" is what causes Christians to "awaken" to see that forgiveness is available to all who have faith that Jesus' sacrifice atones for all sins.
This salvation is not possible through believers' imperfect good works which are simply evidence of faith, only through Christ's sacrifice which is free to all.
He lays out twelve tests of true conversion, including ways of measuring allegedly fruitful works.
"All the virtues of the Lamb of God, His humility, patience, meekness, submission, obedience, love and compassion, are exhibited to our view in a manner the most tending to move our affections of any that can be imagined."
"Religious Affections" remains popular and modern day evangelists and writers such as Tim Keller and John Piper often refer to this and other Edwards works as models for their ministry.