It was not the Apologia. It was the last section, "Persons who inspire anxiety", of Lecture 11 in "Certain Difficulties felt by Anglicans in Catholic Teaching". Doesn't this just speak of many people in a certain situation today?
There is but one set of persons, indeed, who inspire the Catholic with special anxiety, as much so as the open sinner, who is not peculiar to any Communion, Catholic or schismatic, and who does not come into the present question. There is one set of persons in whom every Catholic must feel intense interest, about whom he must feel the gravest apprehensions; viz., those who have some rays of light vouchsafed to them as to their heresy or as to their schism, and who seem to be closing their eyes upon it; or those who have actually gained a clear view of the nothingness of their own Communion, and the reality and divinity of the Catholic Church, yet delay to act upon their knowledge. You, my dear brethren, if such are here present, are in a very different state from those around you. You are called by the inscrutable grace of God to the possession of a great benefit, and to refuse the benefit is to lose the grace. You cannot be as others: they pursue their own way, they walk over this wide earth, and see nothing wonderful or glorious in the sun, moon, and stars of the spiritual heavens; or they have an intellectual sense of their beauty, but no feeling of duty or of love towards them; or they wish to love them, but think they ought not, lest they should get a distaste for that mire and foulness which is their present portion. They have not yet had the call to inquire, and to seek, and to pray for further guidance, infused into their hearts by the gracious Spirit of God; and they will be judged according to what is given them, not by what is not. But on you the thought has dawned, that possibly Catholicism may be true; you have doubted the safety of your present position, and the present pardon of your sins, and the completeness of your present faith. You, by means of that very system in which you find yourselves, have been led to doubt that system. If the Mosaic law, given from above, was a schoolmaster to lead souls to Christ, much more is it true that an heretical creed, when properly understood, warns us against itself, and frightens us from it, and is forced against its will to open for us with its own hands its prison gates, and to show us the way to a better country. So has it been with you. You set out in simplicity and earnestness intending to serve it, and your very serving taught you to serve another. You began to use its prayers and act upon its rules, and they did but witness against it, and made you love it, not more but less, and carried off your affections to one whom you had not loved. The more you gazed upon your own communion the more unlike it you grew; the more you tried to be good Anglicans, the more you found yourselves drawn in heart and spirit to the Catholic Church. It was the destiny of the false prophetess that she could not keep the little ones who devoted themselves to her; and the more simply they gave up their private judgment to her, the more sure they were of being thrown off by her, against their will, into the current of attraction which led straight to the true Mother of their souls. So month has gone on after month, and year after year; and you have again and again vowed obedience to your own Church, and you have protested against those who left her, and you have thought you found in them what you liked not, and you have prophesied evil about them and good about yourselves; and your plans seemed prospering and your influence extending, and great things were to be; and yet, strange to say, at the end of the time you have found yourselves steadily advanced in the direction which you feared, and never were nearer to the promised land than you are now.