This was the first book written by Mirza Basheeruddin Mahmud Ahmad and company that was vs. the Lahori-Ahmadi’s.  This was in response to Khwaja Kamal-uddin’s speech in Lahore, which happened in Dec of 1914.

Some quotes

“””If one were to define Haqiqi Nabi (real Prophet) as a Prophet who is not an impostor or pretender but a Prophet who has really been sent by God, who bears the title of Nabi in the sense of an accredited messenger of God, agreeably to the sense in which the word is used in the Holy Quran and possesses all the attributes requisite in a Nabi in their proper measure, then in view of such a definition, I would say that the Promised Messiahas was a Haqiqi Nabi, but, of course, I would not give him that name if it is understood to mean that he brought a new Law.” (Al-Qaulul Fasl, page 12).(As quoted in “Truth about the Split”, online edition, pages 196-197,  

“According to us what is meant by the Promised Messiahas being a Zilli or a Baruzi
Nabi, is simply this that his Nubuwwat (prophethood) was attained by virtue of his
pupillage and obedience to the Holy Prophet Muhammadsa, whereas the previous
Prophets attained this rank directly, and the words do not imply that the Nubuwwat
(prophethood) of the Promised Messiahas was something of the nature of an honorary
title which had no real substance behind it, or that his Nubuwwat did not entitle him to
the status and privileges of Prophets.” (Al- Qaulul Fasl. p. 18)(As quoted in “Truth about the Split”, online edition, pages 196-197,

“””The Promised Messiahas has called himself Ahmad, and said that it was he who was the real object of the prophecy, because he said that in this passage (the verse Ismuhu Ahmad in
Chapter Al-Saff of the Holy Quran), there is a prophecy concerning Ahmad, alone, whereas the Holy Prophet was both Ahmad and Muhammad.” (Al- Qaulul Fasl, page 27).(As quoted in “Truth about the Split”, online edition, page 198,

“In short, the reference quoted above proves that until the publication of Tiryaq-ul-Qulub, [the writing of] which began in August 1899 and ended on 25 October 1902, his belief was that he has partial excellence over Jesus and that his being called prophet means a kind of partial pro­phethood and deficient prophethood. But afterwards … he learnt from God that he excels the Messiah in all qualities and is not the recipient of any partial prophet­hood, but is a prophet. … Thus it is absolutely unallow­able to use any writing before 1902 as evidence because the Promised Messiah has given the decision that, as regards his belief about prophet­hood which he expressed in Tiryaq-ul-Qulub, later revela­tion made him change it.” (Al-Qaul-ul-Fasl, p. 24. This book is on their website in the collection Anwar-ul-‘ulum, v. 2, book no. 8. See page 285.)