The following text is taken from the first volume of the "Life of Anne Catherine Emmerich", chapter 41. I have added my own comments in blue.
"On the first Sunday of Advent, 1819, a poor old Jewess came begging an alms of Sister Emmerich for her sick husband; she was kindly received and to a few silver pieces Sister Emmerich added words that both touched and consoled her. It was not the first time the poor woman had sought the couch of suffering for relief in her own sorrows, and she had never come in vain. On this occasion, the invalid was seized with such compassion for the poor Jews that she turned to God with ardent prayers for their salvation. She was most wonderfully heard. Shortly after, she related the following vision in which her task was assigned for the beginning of the ecclesiastical year, prayer not only for the poor Jewess, but also for her whole race.
“It seemed to me that the old Jewess Meyr, to whom I had often given alms, died and went to purgatory, and that her soul came back to thank me as it was through me that she was led to believe in Jesus Christ.[It is clear from this statement that she came to a belief in Jesus Christ; the manner of this faith becomes clearer further on.] She had reflected that I had so often given her alms, although no one gives to the poor Jews; and she had thereby felt a desire spring up in her heart to die for Jesus, if faith in Jesus were the true faith. It was as if her conversion had already taken place or would take place, for I felt impelled to give thanks and to pray for her.[So she was open to Christ in the sense that if faith in Christ were the true faith, then she would give herself whole heartedly to him. Blessed Anne Catherine Emmerich describes this desire of hers being "as if her conversion had already taken place." The mere openness and seeking of the true faith thus is a certain kind of faith. This echoes what we already heard from St. Augustine all the way back in the fifth century:
“The Apostle Paul has said: 'A man that is an heretic after the first and second admonition reject, knowing that he that is such is subverted and sins, being condemned of himself.' But though the doctrine which men hold be false and perverse, if they do not maintain it with passionate obstinacy, especially when they have not devised it by the rashness of their own presumption, but have accepted it from parents who had been misguided and had fallen into error, and if they are with anxiety seeking the truth, and are prepared to be set right when they have found it such men are not to be counted as heretics.”]
Old Mrs. Meyr was not dead. But her soul had been disengaged from the body in sleep that she might inform me that, if she died in her present sentiments, she would go to purgatory. Her mother, she said, had also received an impression of the truth of Christianity, and she certainly was not lost. I saw the soul of her mother in a dark, gloomy place, abandoned by all. She was as if walled up, unable to help herself or even to stir, and all around her, above and below, were countless souls in the same condition. I had the happy assurance that no soul was lost whom ignorance alone hindered from knowing Jesus, who had a vague desire to know Him, and who had not lived in a state of grievous sin.
[Bl. Anne Catherine Emmerich says that she had the assurance that no soul was lost who ignorance alone hindered from knowing Jesus, provided that it has a "vague" desire to know him, and has not lived in the state of grievous sin. A couple of points can be drawn out from this:
1) As the Holy Office states in the letter to the Archbishop of Boston, God has willed that the effects of those means necessary for salvation may be attained by a desire for those means, when the means themselves cannot be had actually. Bl. Emmerich makes this same point, since she says that the desire to know Jesus can save a soul who does not actually know Jesus.
2) It is also clear that this desire to know Jesus does not have to be absolute, since it was said earlier that the Jewish woman desired to die for Jesus, on the condition that faith in Him was the true faith. Thus one honestly seeking the truth can desire to know Jesus on the condition that knowing Him is the true faith.
An implication from the second point is that if there were a person honestly seeking the truth, and was willing to die for that truth, that would be sufficient for their salvation, even if they did not yet know that Christ was the one who is the truth.]