Are there any modern churches that subscribe to the Donatist heresy? Back in the late 300s, the big heresy was Donatism.  The basic idea was that if a Priest cracked under the pressure of persecution that it somehow "proved" he was never really worthy of administering the sacraments in the first place, and therefore any baptism, eucharist, or other thing he administered was somehow invalid.

Augustine, however, issued a powerful defense of the idea that a sacrament doesn't depend on the one administering it, but rather the one receiving it.  In reading a recent question about the Waldensians, however, I was surprised to see that they really were much-later Donatists.

The question then, is this - Are there any modern / extant churches that subscribe to this?
Depending on how strictly you define Donatism (sacraments and their efficacy aren't a "given" for most modern movements), it could be argued that many historical movements have been (and are) Donatist when they create a class of Christians who are superior to others and denounce others as non-believers because they are not as devoted. Some have argued that the Anabaptist movement was Donatist, and others have argued that various hyper-conservative movements within denominations or within other movements are Donatist. This can be as subtle as making a distinction between "Spirit-filled" and "nominal" believers, or by other class distinctions whereby one group is repudiated as being inferior because they are less dedicated or do not share the same experiences as the "superior" group.

I'm glad that the apostles didn't adopt that approach, because we'd only be able to read the gospel of John if that were the case ;)