Halakhah su Levitico 25:26

And also from the laws of the commandment is that which they, may their memory be blessed, said (Arakhin 30a) that one who sells a field of holding and he had other lands - that is, land that he purchased or [others] gave to him as a gift - and [then] he sells those fields to redeem his field of holding that he sold, he is not heeded. As it is written in the section of the field of holding (Leviticus 25:26), "but he finds enough to redeem" - and the explanation comes about it, that it is until he finds something that was not available to him at the time of the sale. And so [too,] if he borrowed and wished to redeem with that loan, he is not heeded - as it is stated, "and his hand reached," and not that he borrowed.