I think you are mistaken here. Not arahants or enlightened beings have the three knowledges. There were many disciples of the Buddha (and even a few rare cases of lay people) who attained full spirtual realization without experiencing with the "divine eye" rebirth of beings and seeing one's own past lives. In fact, these two knowledges were described to been having attained by non-buddhist practioners, but they were not enlightened.green wrote:A Buddhist should NEVER argue about rebirth without discussing Dependent causation - to discuss it without a detailed discussion of this cycle would be like falling into a trap or wrong views.
The Arahant gains the "Tevijja" or three knowledges -- which includes the knowledge of past lives.