That thou mightest know the certainty
The end the evangelist had in writing this Gospel, and sending it
to Theophilus, was, that he might be more strongly assured of and
more firmly established in the truths of the Gospel. The Vulgate
Latin, Syriac, and Arabic versions render it, "that thou mightest
know the truth"; that is, the certain truth of things: the truth
he did in some measure know before, but Luke's view was, that he
might have a more certain knowledge of it; both truth, and the
certainty of it may be intended: so the Hebrew word, (hnwma) , signifies both truth and
firmness; and the word here used signifies such a certain
evidence of things, as may be safely depended on; even
of those things, wherein thou hast been
instructed;
or catechised, signifying, that he had been hitherto taught, as a
catechumen, the rudiments, and first principles of the Christian
religion, by word of mouth; and he had taken them in upon the
evidence they came with, and the authority of those that
instructed him in them; and now he sent him in writing this
account, to increase his knowledge, strengthen his faith, and to
give him such a sure proof of things, as might preserve him safe
in the belief of them, from all doubting and defection. Having
finished his preface, he proceeds to the narrative itself, which
begins as follows.