Simplify the following text for a Grade 12 native English-speaking person.
Original: The first general council at Constantinople in 381 in canon VII and the third general council at Constantinople in 680 in canon XCV declared the baptism of Sabellius to be invalid , which indicates that Sabellianism was still extant .
Simplified: The second general council at Constantinople in 533 AD declared the baptism of Sabellius to be invalid , which indicates that Sabellianism was still around .