CCC 2089

Incredulity is the neglect of revealed truth or the willful refusal to assent to it. "Heresy is the obstinate post-baptismal denial of some truth which must be believed with divine and catholic faith, or it is likewise an obstinate doubt concerning the same; apostasy is the total repudiation of the Christian faith; schism is the refusal of submission to the Roman Pontiff or of communion with the members of the Church subject to him." CIC, can. 751: emphasis added.

Read the full chapter 1. You Shall Love the Lord Your God with All Your Heart, and with All Your Soul, and with All Your Mind ¶2083–2195

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