Recall that Norman Geisler attempted to defend Ergun Caner in this way (link to defense):
7. Ergun claimed his father had many wives and two half-brothers and two half-sisters, but there is no evidence for the half-brothers.Ergun's father did have two wives - one after the other - not many wives. Yet Ergun repeatedly claimed his father had "other wives" besides Ergun's mother. "Two wives" does not support that claim, even if it could somehow be used to support the "many wives" claim. Ergun also claimed that his father immigrated with "wives." That also does not match the two serial marriages story.
Response: Ergun’s father did have two wives, having divorced the first one. He had three sons by his first wife (Ergun and his two brothers). So, Ergun has two full brothers and two step-sisters (from his father’s second wife). While speaking quickly on one occasion, he mistakenly called his brothers his “half” brothers. This is hardly evidence of an attempt to embellish or deceive. After all, he had the right number of each sibling, and he didn’t claim to have ten brothers or sisters!
Furthermore, Ergun did not use the "half-brothers" claim only once. He used it at Calvary Chapel Old Bridge and in two different messages at Ashburn Baptist Church.
And Ergun was not referring to his brothers when he said it. At Calvary Chapel Old Bridge, Ergun said "I have half-brothers and sisters who don't know Jesus." Likewise, at Ashburn Baptist on June 3 Ergun said, "And so in 1978, my father, my mother, my two brothers, my father's other wives, and my half-brothers and sisters came to this country." And then again at Ashburn Baptist on June 5 Ergun said "I have half-brothers and half-sisters in Chicago, in New York, and in Turkey, who live here, who are still lost as geese" and again a few second later "How dare I give up! My half-brothers, my uncles, my aunts, How dare I give up!"
In short, while part of what Geisler wrote in defense of Ergun on this point is true ("two wives" and two half-sisters) much is untrue: it was not just once that he referred to "half-brothers" and he was not referring to his own brothers when he did so. Even the true part falls short of defending the "other wives" claim or - bluntly speaking - even the "many wives" claim.
This and a number of other serious problems with Caner's autobiographical claims are documented in the Caner Affair article (link), which is mostly an index to other posts that document a lot of what Ergun Caner has said. Currently, the list of source posts is around 54 or so (and growing), but some of those source posts deal with more than one speaking occasion. For example, Dr. Caner has spoken multiple times at some churches, and generally those messages are grouped together in a single source post.