A player reached the crown of command with the amulet that prevents casting spells. he then ditched the item so he could cast the command spell. after the command spell was cast he then picked the item back up to prevent spells being cast on him on other players turns. Is this legal as he is essentially dropping and picking up the same item up on the same turn?

n/m found the answer in the rules

"A character may ditch any of his Followers or Objects at any
time by leaving them faceup in the space he occupies. If a
character ditches any Followers or Objects, he cannot take
them back during the same turn."

so he was playing it wrong.

related question: If a character drops an item on a regular space, such as woods for example, at the beginning of his next turn, if the item is still there, can he pick it up? or does he have to move and land back on the space?

Gonad the Ballbarian said:

You don't interact with the space you start in, so need to move away, then return to get the item back (barring CoC).