John Wesley on Deuteronomy 15:2

Every creditor - Here is, a law for poor, insolvent debtors. Every seventh year was a year of release, when among other acts of grace, this was one, that every Israelite, who had borrowed money, and had not been able to pay it before, should this year be released from it. And tho' if he was able, he was bound in conscience to pay it afterwards, yet it could not be recovered by law. His brother - This is added to limit the word neighbour, which is more general, unto a brother, in nation and religion, an Israelite. The Lord's release - Or, a release for the Lord, in obedience to his command, for his honour, and as an acknowledgment of his right in your estates, and of his kindness in giving and continuing them to you.