There must be also heresies— There must be even heresies. Hence it seems evident, that heresy is spoken of as something worse than the schisms or divisions mentioned 1 Corinthians 11:18 but whether it be an evil entirely of a different kind, or only of a higher degree, is not so clear from this passage. The word 'Αιρεσις may probably here signify a party of people separated from their brethren, and forming what is called a distinct denomination; whereas there may be a schism without separation, if the people assembling together have uncharitable contentionswith each other; which was the case with these schismatical Corinthians. See Doddridge
Related Commentaries of 1 Corinthians 11:19
1 Corinthians 11:19
19 For there must be also heresiese among you, that they which are approved may be made manifest among you.