Expository preaching must remain faithful to the text of Scripture.  There are two ways, says John Stott, in which the expositor might depart from his text: forgetfulness and disloyalty.

G. Campbell Morgan, himself a fine expositor, noted of Benjamin Jowett, Master of Balliol College Oxford that he

declared that it was his habit to write his sermons, and then choose a text as a peg on which to hang them.  I am quite free to say…that the study of his sermons will reveal the accuracy of his statement, and show the peril of the method.

Another preacher would give our his text and then say,

“This is my text.  I am now going to preach.  Maybe we’ll meet again, my text and I, and maybe not.”

But worse still than this candid indifference to the text is the pretence of expounding when in fact one is exploiting the text.  Such false teachers are roundly condemned in the New Testament as ‘swerving’ from the truth, for ‘peddling’ God’s word, for ‘perverting’ the gospel by altering its content, and for ‘twisting’ the Scriptures.  Paul, in contrast, declared that he had ‘renounced disgraceful, underhand ways’, and that he refuses to ‘tamper’ with God’s word, and that instead he relies on ‘the open statement of the truth’.

In the words of A. Vinet,

a passage of Scripture has a thousand times served for a passport to ideas which were not scriptural.

Sometimes, the misappropriation of a text can occur as a result of opportunism.  For example, when W.R. Matthews, Dean of St Paul’s Cathedral, wished to emphasise the need to go on from victory to reconstruction after the cessation of hostilities at the end of the 1st World War took as his text Rom 8:37 (‘we are more than conquerors’).

At other times, a text is misused because the preacher is riding his theological hobby-horse.  A certain preacher had such pronounced views about baptism that forced the subject into every sermon:

My text is “Adam, where are you?”  There are three lines we shall follow.  First, where Adam was; secondly, how he was to be got from where he was; and thirdly and lastly, a few words about baptism.

Then there were the ‘Puseyites’ who would never leave Mt 18:12 (“if he neglect to hear the church…’) alone, thinking that it lent support to their high view of the Church’s authority.

From all such carelessness and conjuring tricks, may the good Lord deliver us.

Based on Stott, I believe in preaching, 129-132.