quandy57:
I think everyone has seen a catholic speaker speak heresy or blasphemy to an audience
Heresy and blasphemy are quite serious charges.
Catechism of the Catholic Church - Paragraph # 2089
Let us know how the Church defines
" 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;
Catechism of the Catholic Church - Paragraph # 2148
2148 Blasphemy is directly opposed to the second commandment. It consists in uttering against God - inwardly or outwardly - words of hatred, reproach, or defiance; in speaking ill of God; in failing in respect toward him in one’s speech; in misusing God’s name. St. James condemns those “who blaspheme that honorable name [of Jesus] by which you are called.” The prohibition of blasphemy extends to language against Christ’s Church, the saints, and sacred things. It is also blasphemous to make use of God’s name to cover up criminal practices, to reduce peoples to servitude, to torture persons or put them to death. The misuse of God’s name to commit a crime can provoke others to repudiate religion.
Blasphemy is contrary to the respect due God and his holy name. It is in itself a grave sin.
I have heard some things that are silly, for instance I once heard the sermon that the real miracle of the loaves and fishes was sharing. While this is a well worn idea, it does not rise to heresy.
If you encouter someone speaking true heresy or blasphemy, first make an appointment to speak with them (or in the case of a traveling speaker, reach out via phone or email).
“I understood you to say XYZ. Could you please explain this to me because the Catechism (or other official document) states ABC”.
If they persist, go to the Bishop.