because they just didn't hold with such nonsense 里面的just 是什么意思。

ADV（用于加强语气，表示生气、赞美、肯定等）硬是，就是，简直You use just to emphasize the following word or phrase, in order to express feelings such as annoyance, admiration, or certainty.

because they just didn't hold with such nonsense.
因为他们就是不相信那些废话。

仅供参考，谢谢欣赏