"In Theravada Buddhism, Buddha's omniscience is claimed only with respect to diagnosing the cause of dukkha and prescribing the way of removing it, the further wrinkle being that the Buddha unlike other arhants, knew this remedy in each individual case, whereas the arhants by and large relied on the four noble truths, which in any case has been had been propounded by Buddha."
January 1, 1970
https://en.wikiquote.org/wiki/Omniscience