Hi Alex, the next bit is very instructive as to why the arahant should do this:Alex123 wrote: Does Arahant have clinging aggregates?Then which things should an arahant attend to in an appropriate way?"
"An arahant should attend in an appropriate way to these five clinging-aggregates as inconstant, stressful, a disease, a cancer, an arrow, painful, an affliction, alien, a dissolution, an emptiness, not-self. SN22.122
By way of contrast, when the reason for why one ought to contemplate the clinging-aggregates was given for a virtuous monk, a stream-enterer, a once-returner and a non-returner, every time it was for the sake of progressing to the next level of realisation. But for the arahant (it seems to me, to be) not so much a matter of 'why' as 'why not?'Although, for an arahant, there is nothing further to do, and nothing to add to what has been done, still these things — when developed & pursued — lead both to a pleasant abiding in the here-&-now and to mindfulness & alertness."
That's my take on it. If I've misrepresented anything - someone please correct me!