Is a schismatic priest's Mass valid?

[Rockin_Catholic]

I have recently become aware of a situation where a priest is celebrating Masses, but is not under the jurisdiction of a bishop. As I understand it, years ago, when the new form of the Mass replaced the traditional Latin Mass, this priest essentially did not believe in the new form of the Mass and believed it would go against his conscience or be wrong for him to offer this new form of the Mass. Therefore, he broke from the Bishop and the diocese so that he would not be forced into celebrating the new form of the Mass. My questions: Are his Masses still valid? Is it wrong for Catholics to attend his Masses?

 

[Fr.Charles_Grondin]

If the priest is not part of a community in communion with the Holy Father then his Masses are illicit. Once a priest always a priest, so he can still say a valid Mass. However a Catholic does not fulfill their Sunday obligation by attending a schismatic Mass.