I'm sorry if this is too specific or unclear, if it's a bad question i can delete it. I'm really unclear on how なければ is functioning here, and how と in this case is functioning after 子どもたち. (also i'm not sure if 尊敬すべきこのクラスを is still part of the sentence) is this a case in which "なければならない" is implied?
1 Answer
You're right. The ~~なければ here is a shortened form of ~~なければならない and means "have to~~" "should~~". And 清らかな子供たち, それを無条件で愛する教師, and 尊敬すべきこのクラス are the objects of 信じなければならない. (This is an inversion/倒置 of 清らかな子供たちと、それを無条件で愛する教師、尊敬すべきこのクラスを、信じなければ。)