I'd like to intervene here with the historical question: when did the Church of Jesus Christ of Latter-day Saints begin to teach its members to say "the Church is true"?
I ask because that is a very strange kind of thing to say. In the normal usage of modern English, being "true" is something that you can affirm or deny about a proposition, that is some words affirming that something is the case, such as "Jane has blonde hair" or "Nicaragua is a country in Central America" which are examples of propositions that one might say are "true"; however, faced with propositions such as "the moon is made of green cheese" or "Donald Trump is a Mexican immigrant", one might say that those propositions are "false". For this sense of the word, the following examples are given in the Oxford English Dictionary:
4.
a. Of a statement, idea, belief, etc.: in accordance with fact; agreeing with reality; correct.
a1250 Wohunge ure Lauerd in R. Morris Old Eng. Homilies (1868) 1st Ser. 283 A swete ihesu þu oppnes me þin herte for to cnawe witerliche and in to reden trewe luue lettres.
c1275 (▸?a1200) Laȝamon Brut (Calig.) (1963) l. 2217 Belin ihærde sugge þurh summe sæg treowe. of his broðer wifðinge.
c1300 St. Bridget (Laud) l. 10 in C. Horstmann Early S.-Eng. Legendary (1887) 192 (MED) Heo scholde..At a certeyn dai þarof trewe a-countes ȝelde.
▸ c1384 Bible (Wycliffite, E.V.) (Douce 369(2)) (1850) John xxi. 24 We witen, for [a1425 L.V. that] his witnessing is trewe.
c1400 (▸?a1387) W. Langland Piers Plowman (Huntington HM 137) (1873) C. i. l. 100 Al þe wordle [emended in ed. to world] wot wel hit myȝte nat be trywe.
1490 W. Caxton tr. Foure Sonnes of Aymon (1885) xvii. 396 ‘Syr, wyte that charlemagne is come wyth his oost’... ‘Is it true?’ said mawgis.
a1529 J. Skelton Howe Douty Duke of Albany in Wks. (1568) f. ii These tidinges newe Whiche be as trewe As the gospell.
1597 A. Montgomerie Cherrie & Slae 878 I..Thocht all thair tales wer trewe.
1608 A. Willet Hexapla in Exodum xxxiv. 839 The truer opinion.
1650 tr. Nicholas of Cusa Idiot ii. 32 I labour to frame a true conception of God.
1722 J. Bingham Origines Ecclesiasticæ IX. xx. vii. 163 The Fact was too true, and the Charge too well-grounded to be denied of them all in general.
1759 S. Johnson Prince of Abissinia II. xlvii. 158 The same proposition cannot be at once true and false.
1854 D. Lardner Hand-bk. Nat. Philos. & Astron. (new ed.) I. 16 This will be true, however shallow the vessel..and however narrow the tube.
1870 A. Helps Casimir Maremma II. xxxii. 123 Marvellous to relate the rumour proved to be true.
1938 H. Kantorowicz & W. W. Buckland Stud. Glossators Rom. Law ix. 208 No true notion of the lost work could be formed.
1958 C. Achebe Things fall Apart v. 38 Nwoye's younger brothers were about to tell their mother the true story of the accident.
2010 N.Y. Times 10 Nov. b21/5 It's a ridiculous claim and simply not true.
I am however racking my brains to try to think of an example of somebody affirming that an institution or organisation is "true" in anything resembling that sense. There are other senses, such as 'loyal', 'reliable' and so on, but those are normally used of individual persons. No-one ever says that something like the Republican Party, the United Nations, or Microsoft is 'true', do they?
So: who first taught Mormons to say "The church is true", and why did they do that?
(There is an interesting discussion of the uniqueness of this LDS practice by Kevin Barney here:
https://bycommonconsent.com/2015/01/21/ ... h-is-true/
... but it does not address my principal question -
Who started this, when, and why? Can anybody here answer that?