Severus of Antioch condemned Chalcedon and considered Chalcedonianism a heresy. It is worth noting that when he did, Constantinople III has not been convened yet. Many Chalcedonians were finding difficulty saying “the Word suffered in flesh.”

After Constantinople III, a lot of political moves took place making the possibility of trusting Chalcedonians impossible.

At such point, Severus was no longer concerned with Chalcedonians so much as he was with Julianists and other heretics within the non-Chalcedonian camp.

Today, ALL Chalcedonians say that in their hymns so the fear of THEN separating/dividing natures should be far less on our end.

Regarding dealing with schismatics, Chalcedonians would reanoint non-Chalcedonians coming back and reordain their clergy.

Some non-Chalcedonians, in retaliation, wanted to hold the same policy. Unlike the puritans of non-Chalcedonians and the extremist policy of Chalcedonians, Severus was open minded enough to condemn the practice of repeating sacraments performed among chalcedonians.

In doing so, he was citing Cyril and Timothy II of Alexandria. He called non-Chalcedonian puritans the self-made religion of reanointers and anathematized them. In Severus’ book, no sacrament was to be repeated.

So yes, Severus condemned Chalcedon. But no, he was not close minded and was in fact more open minded than Chalcedonians and some non-Chalcedonians of his time.

There’s more to his open mindedness on pastoral issues. But that’s enough for now.

If you want more, read his letters translated by E W Brooks.