Translated by Allan Menzies.
From the Fifth Book.
From the Preface. 
You are not content to fulfil the office, when I am present with you, of a taskmaster to drive me to labour at theology; even when I am absent you demand that I should spend most of my time on you and on the task I have to do for you.  I, for my part, am inclined to shrink from toil, and to avoid that danger which threatens from God those who give themselves to writing on divinity; thus I would take shelter in Scripture in refraining from making many books. For Solomon says in Ecclesiastes,  "My son, beware of making many books; there is no end of it, and much study is a weariness of the flesh." For we, except that text have some hidden meaning which we do not yet perceive, have directly transgressed the injunction, we have not guarded ourselves against making many books.
[Then, after saying that this discussion of but a few sentences of the Gospel have run to four volumes, he goes on:]
 From the Philocalia.
 This is addressed to Ambrose, who was at the time absent from Alexandria. Cf. book i. chap. 6, p. 299.
 xii. 12.
Reference address : https://www.ellopos.net/elpenor/greek-texts/fathers/origen/john-commentary.asp?pg=114