What is the effect of revoking permission to take possession after possession has already occurred?

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If the pledgor revokes permission after possession has taken place, the revocation is without effect because the pledge has become obligatory due to the connection of possession with it. In any instance where the obligation of the pledge is removed due to the removal of possession, permission for a second possession is considered, as it is a possession that makes the pledge obligatory, similar to the first. Actions indicating permission substitute for explicit permission, such as sending the slave to the pledgee, or returning something taken from the pledgee back into the pledgor's hand. These actions serve as proof of permission, which is sufficient, analogous to inviting people to food and presenting it before them, which serves as permission for them to eat.