When did Jim Jones first ask the members of Peoples Temple to call him “Father” or “Dad”?

Jones modeled the Father/Mother language after that of Father Divine in Philadelphia, whom Jones visited in the mid-1950s, which meant the practice began while the Temple was still in Indianapolis.

From Jeff Guinn in The Road to Jonestown:

In late 1956 or early 1957, Jim Jones requested a meeting with Father Divine at Woodmont, the first of many such meetings. “He adopted some of his new mentor’s affectations. Peoples Temple members were encouraged to address him as Father and Marceline as Mother” (Guinn 2017: 88).

From John R. Hall in Gone From the Promised Land:

“From the onset of Jones’s Philadelphia connection, the Indianapolis church took on many of the trappings of Peace Mission life. . . . Jim Jones would become ‘Father’ or ‘Dad,’ like Father Divine and like many more conventional Black Pentecostal preachers as well” (Hall 1987: 51).

From C. Eric Lincoln and Lawrence H. Mamiya, “Daddy Jones and Father Divine: The Cult as Political Religion” in Peoples Temple and Black Religion in America:

“Like Father Divine, Jones urged his parishioners in Indianapolis to call him ‘Father’ or ‘Dad.’ This use of paternalistic terminology is of course not unusual in the Christian tradition where ‘father’ or some synonymous term is a common designation for ‘pastor.’ In the black religious tradition, counterpart terminology may also be applied to the wife of the leader—especially if he himself is highly venerated and if she is considered properly complementary. Impressed by the co-regency of ‘Mother Divine’ in Father Divine’s movement, Jim Jones encouraged his followers to refer to his wife Marceline, as ‘Mother Jones.’ In the black cults a leader who became Father or Daddy was more than a mere pastor. He represented absolute authority and commanded absolute obedience” (Lincoln and Hall, 2004: 39).