Midrasch zu Mischlej 20:16

(Fol. 115) Our Rabbis were taught: (Deut. 24, 10) Thou shalt not go into his house to take his pledge; i.e., in his house only you shall not go; you may, however, go into the house of the one who guaranteed, and so says the passage (Pr. 20, 16) Take away his garment because he has been surety for a stranger. And it is also said (Ib. 6, 1-4) My son, if thou hast become surety for thy friend, which means, if you were surety, then give him that which you have assured, and if you have no money, see some friend, who will ask him to favor you.