Gemara

(Mishnah): If Reuven received a deposit, stole or borrowed from Shimon in a Yishuv (settled area), he may not return to him in the Midbar (wilderness);

Contradiction (Beraisa): A loan may be paid anywhere. An Aveidah or deposit is returned only in its place.

Answer (Abaye): The Beraisa means that one may demand payment of a loan anywhere. One may demand an Aveidah or deposit only in its place.

Gitin 74b (Mishnah): At first, one who bought a Bayis Ir Chomah (a house in a walled city) would hide on the last day that the seller could redeem it. Hillel enacted that the seller may deposit the redemption money in a chamber and forcibly enter the house.

Version #1 (Rava) Inference: If one gave a Get 'on condition that you give to me 200 Zuz', the Get is valid only if he takes the money willingly.

Hillel needed to enact that one can pay the buyer Bal Korcho. This implies that without an enactment, paying Bal Korcho is invalid.

Objection (Rav Papa): Perhaps the enactment was for when the buyer is away, but when he is here, giving Bal Korcho works!

Version #2 (Rava) Inference: If one gave a Get 'on condition that you give to me 200 Zuz', the Get is valid whether or not he takes the money willingly.

Hillel needed to enact only for when the buyer is not here. When he is here, whether or not he consents to accept the money, the redemption works!

Objection (Rav Papa): Perhaps it is valid only when he consents to accept the money. Hillel enacted what was needed.

Kidushin 12b: Shimon was Mekadesh Rachel with a myrtle mat. People remarked that it is not worth a Perutah. Shimon said 'she should be Mekudeshes with the four Zuzim inside.' She took it and was silent.

(Rava): Silence after the money was already given has no effect:

(Beraisa): If Reuven told Leah 'take this money for a deposit', and after he gave it he said 'be Mekudeshes to me through it', if she wants, she is Mekudeshes. If she does not want, she is not Mekudeshes.

Wanting is saying 'yes'. Not wanting is being silent.

Question (Rav Huna): In the Beraisa, she is responsible for the money (it was a deposit), so she is afraid to throw it back. Here, the money was given for Kidushin. If she does not accept, she should throw it back!

Objection (Rav Achai): Perhaps she errs, and thinks that even regarding Kidushin, if she throws the money and it is lost, she is responsible!

Rishonim

Rif: If one found an Aveidah or accepted a deposit in a Yishuv, the owner cannot demand it from the (finder or) Shomer in the Midbar if he does not have it with him. Similar, if the Shomer has it and the owner does not want to take it back in the Midbar, the Shomer cannot force him. He has responsibility until he returns it in a Yishuv, like he deposited.

Rambam (Hilchos She'elah 7:11): One can claim a deposit or Aveidah only in its place. If David deposited with Levi in Yerushalayim, he cannot claim from him in Nov. If he returned to him in Nov, he receives it. If he deposited in a Yishuv and Levi returned in in the Midbar, David need not accept it. He says 'you have Achrayus until you return it to me in a Yishuv, like I deposited with you in a Yishuv.'

Magid Mishneh: We learned that one may demand an Aveidah or deposit only in its place. This implies that the Shomer may return it anywhere, Bal Korcho of the owner. If he accepted to guard it for a set time, he cannot force him to accept it back within this time.

Rosh (Gitin 7:7): Obviously, a Shomer can repay Bal Korcho of the owner. Only in the Midbar he cannot force him to accept payment.

Rashba (Kidushin 13a DH Savra): Initially, we assumed that Rachel knew the Halachah. If so, why didn't she throw it back and say 'here is yours'? The Ra'avad says that he had deposited with her for a set time, so she could not give it back. This is difficult. The Beraisa did not specify. Why should Rav Huna assume that it discusses a deposit for a set timem in order to challenge Rava? The Gemara should have specified. Also, I am unsure about this. Even if the deposit was for a set time, why can't she retract in the middle? A Shomer Chinam should be no more liable than a worker, who can retract in the middle of the day! The Ra'avad answered that she was concerned lest it get lost before it reaches him. Some say that she thinks that since she accepted to guard the deposit, she is liable if she throws it, but even she knows that she is exempt for Kidushin money, since she never agreed to guard it. The Ramban says that if she throws a deposit, she is liable. She accepted to return it to his hand. If she said 'take yours', and he did not want to, if she said 'here is yours' and threw it in front of him, she would be exempt. If she was silent and threw it, she is liable. I (the Rashba) am unsure if she must return it to his hand. Granted, a debt must be returned to his hand, or the lender can authorize the borrower to throw it. This is because a loan is in the borrower's Reshus, but a deposit is in the owner's Reshus. It should suffice to put it in his four Amos!

Tumim (6): The Magid Mishneh and Ra'avad hold that a Shomer cannot return the deposit early Bal Korcho of the owner. The Rashba disagrees, for Bnei Yisrael are slaves only to Hash-m. This applies to a Shomer Sachar, who must guard very well. A Shomer Chinam must merely not be negligent. He is not like a slave at all!

Ketzos ha'Choshen (74:1): The Ra'avad and Magid Mishneh hold that a Shomer cannot return the deposit early, for Shmirah is unlike a job. It is acceptance of liability for loss to the deposit. One can retract early from working for an Iska, but not from responsibility to guard it.

Poskim

Shulchan Aruch (CM 293:1): One can claim a deposit only where he deposited it. If he deposited in Teveryah he cannot claim it in Tzipori However, whenever the Shomer wants to return it, the owner must accept it. Even if he returned it Bal Korcho, it is returned and he is exempt.

Shach (1): Gidulei Terumah asks what is the Chidush of the Mishnah. I say that in the Midbar, even if the Shomer has money or a Kli just like the deposit, he need not give it in place of the deposit.. Sefer ha'Terumos 30:1:2 says that David cannot make Levi swear about a deposit even if he says 'perhaps you have it here.' Surely, the word 'perhaps' is a printing mistake. If not, it is no different than a loan, and it is no Chidush. A Safek claim does not obligate swearing. Why did he need to add 'presumably, the Shomer did not bring it'? Rather, it should say 'perhaps he cannot make him swear about a deposit, even if he says 'surely you have it here.''

Shach (74:3): Shiltei ha'Giborim was unsure if money owed for wages or a sale is like a loan, or like a deposit. Surely, it is like a loan. A deposit is different because the Shomer was supposed to leave it in its place!

Shulchan Aruch (ibid.): If he deposited an item for a set time, the Shomer cannot force him to accept it back within this time.

Shach (5): This is even in a Yishuv (Shiltei ha'Giborim 44a 2, SMA 4). This is obvious.

Ketzos ha'Choshen (2): There is a lien on a Shomer's property to pay if the deposit will be stolen or lost through negligence. A Shomer Sachar retains responsibility for these even if he returned it before the time he accepted. However, if it was lost through negligence, the owner bears the loss himself. Since he accepted it willingly, he is no less than a Shomer Chinam. If he returned it before the time Bal Korcho of the owner, the owner is not even a Shomer Chinam, and the Shomer is fully liable like before.

Shulchan Aruch (74:1): A caravan is considered like a Yishuv.

Source: Tosefta 10:14, cited in Beis Yosef (3).

SMA (4): There is no danger of theft in a caravan.