"Christianity cannot compromise on the question of polygamy. If present day Christianity cannot do so, it is to its own detriment. Islam has permitted polygamy as a solution to social ills and has allowed a certain degree of latitude to human nature but only within the strictly defined framework of the law. Christian countries make a great show of monogamy, but actually they practice polygamy. No one is unaware of the part mistresses play in Western society. In this respect Islam is a fundamentally honest religion, and permits a Muslim to marry a second wife if he must, but strictly forbids all clandestine amatory associations in order to safeguard the moral probity of the community."
Only one source that uses the quotation actually has a footnote telling where it supposedly came from in Rev. Graham's published works. Modern Indian Family Law by Werner F. Menski contains a footnote that identifies it as coming from Peace with God, pages 93-94. No English language edition of Peace with God contains the quotation or anything similar.
The original source of the quotation appears to be the pamphlet entitled, The Position of Woman in Islam (A comparative study), published by Islamic Book Publishers of Kuwait in 1982. The quotation attributed to Billy Graham appears on pages 22 and 23. The pamphlet is a reprint in English of two articles, one by Nazhat Afza and the other by Khurshid Ahmed. The Graham quote appears in the Afza article. Throughout this article, the author sometimes uses quotation marks and usually does not. In some cases, the reader cannot tell where Afza is quoting and where he is giving his response to what was quoted. Afza appears to be quoting the first sentence: "Christianity cannot compromise on the question of polygamy." Everything following that sentence in the paragraph appears to be Afza's reaction to the sentence.
The Archives' staff has not been able to find any part of the quotation (not even the first sentence) attributed to Rev. Graham in any his actual books, articles, or sermons.