With most biblical texts however none of these things can be assumed. Many of the texts we have in the Bible are the product of a tradition, with pieces added at different times. Most likely friends or disciples were the first to remember, then write down his preaching. It is also likely that as time passed other generations of disciples added to the collection, and that their additions were filtered through the concerns of their time. Reading such a text we cannot assume cohesion.
Structural cohesion is also of two different sorts.
The conventional nature of the forms of particular genres of text produce cohesion. For example, judgment oracles usually contain an accusation linked to a judgment. So, if a passage contains a message of judgment follows one which accuses, the text will be read as cohesive. Links can be made within a text by the words used. Conjunctions and words which make logical connections also link two parts of a text.