SN 12.35 says:
“Not a valid question,” the Blessed One replied. “Bhikkhu, whether one says, ‘What now is aging-and-death, and for whom is there this aging-and-death?’ or whether one says, ‘Aging-and-death is one thing, the one for whom there is this aging-and-death is another’—both these assertions are identical in meaning; they differ only in the phrasing. If there is the view, ‘The soul and the body are the same,’ there is no living of the holy life; and if there is the view, ‘The soul is one thing, the body is another,’ there is no living of the holy life. Without veering towards either of these extremes, the Tathagata teaches the Dhamma by the middle: ‘With birth as condition, aging-and-death. ’
Why is there no living the holy life when there is the view, ‘The soul and the body are the same,’ and if there is the view, ‘The soul is one thing, the body is another’?