How then shall I know this? Having taken notice of some of you, who are not very attentive, I shall question them privately, when I meet them. And if I find that they retain any of the things that have been spoken (I say not all, for this would not be very easy for you), but even if [they retain] a few things out of many, it is plain I should have no further doubts about the rest. And indeed we ought, without giving notice beforehand, to have attacked you when off your guard. However it will suffice, if even in this way I should be able to attain my purpose. Nay rather, even as it is, I can attack you when you are off your guard. For that I shall question you, I have forewarned you; but when I shall question you I do not as yet make evident. For perhaps it may be to-day; perhaps to-morrow, perhaps after twenty or thirty days, perhaps after fewer, perhaps after more. Thus has God also made uncertain the day of our death. Nor hath He allowed it be clear to us, whether it shall befall us to-day, or to-morrow, or after a whole year, or after many years; that through the uncertainty of the expectation we may through all time keep ourselves firm in virtue. And that we shall indeed depart, He hath said,—but when, He hath not yet said. Thus too I have said that I shall question you, but I have not added when, wishing you always to be thoughtful.