It isn’t theology. It is 1970s pop psychology self-help wrapped in a big smile with the occasional sprinkling of the name “Jesus”.
His father was a real Baptist minister, one with a seminary education, and a pioneer-- he had the first racially integrated church in Houston in the 1950s, Lakewood Church.
Joel has no seminary or theology training. He majored in radio and television communications (big surprise) but did not graduate from college.
His role in Lakewood started when his father’s very popular church began producing a televised service in the early 1980s (there are several Houston area churches with their own tv show including Second Baptist, which I would say was a main “competitor” with Lakewood).
Joel was in charge of tv production. His father died of a heart attack and he took over the church.
I am from the Houston area, so I have been familiar with Lakewood long before it was an international phenomenon.