Quote from PGJ Meiring’s article, “Max Warren and His Seven Rules for a Dialogue Between Christians and Non-Christians. “Actually, the article was originally written in Afrikaaner (“Max Warren en sy sewe reëls vir ’n dialoog tussen Christene en nie-Christene” DEEL 47 # 3 & 4 SEPTEMBER & DECEMBER 2006, P. 588-599.)
The fourth rule/principle is “Identification.” Here is a rough translation of an excerpt of Meiring’s article regarding Identification:

The fourth principle probably asks the most of the conversation partners: the willingness to identify as far as possible with the other person’s life and conditions he lives in. It asks you to understand “the language of his heart”. It does not come naturally of itself: it requires imagination, endurance, humility and much love. Warren loved to refer to the example of the prophet Ezekiel, the prophet to the exiles in Babylon, sent with an all-important message from the Lord. Even though Ezekiel cannot be in the modern sense a “missionary” – after all, he is a prophet sent to his own people – he provides a model for all to consider as the Lord prepared him for his preaching task. Before the prophet was sent to speak, he had to first experience and learn to listen – and this is a lesson that every missionary in our day needs to seriously consider.
In the Authorized Version, Ezekiel 3:15 is translated as: “I came to them of the captivity … and I sat where they sat, and remained astonished among them for seven days “. The Revised Standard Version translates this slightly differently: “I came to them of the captivity … and I sat there overwhelmed among them for seven days”. The emphasis is different, says Warren: the first-mentioned translation emphasizes Ezekiel’s “entering into the experience of the exiles” while the latter “the ‘Overwhelming’ character of what the prophet experienced by joining these exiles where they were ” is emphasized (Warren, 1960: 60vv).
Both emphases are important: first of all, we must meet people where they are, we must “Sit where they sit”. We must understand their situation – their joy and their pain and how these experiences influence their views and beliefs (Warren, 1960: 17). “You and I can not bring men to Christ by whistling to them at a distance. We have to go and meet them, as God does, and psychologically speaking, this means coming to them imaginatively where they imagine themselves to be “(Warren, 1955: 31). The second emphasis, however, is just as important: that we become “Stunned.” We find ourselves speechless because we find it so difficult to really understand the other because their need is so great, and we are struggling to make clear the salvation of Christ because our vocabulary is too inadequate. But also speechless because we experience God already there, that He has already made his voice heard in the situation (Warren,1960: 17).