Complex sentence: This introduced the idea of impressing the token onto the wet bulla before it dried, to insure trust that the tokens hadn't been tampered with and for anyone to know what exactly was in the bulla without having to break it.
Split into simpler sentences: This introduced the idea of impressing the token onto the wet bulla before it dried, to insure trust that the tokens hadn't been tampered with. These impressions from the tokens allowed for anyone to know what exactly was in the bulla without having to break it.