"his neighbor": to exclude others (i.e., gentiles).

"and his brother": to exclude a sojourning stranger (ger toshav).

"because it has been declared shemitah to the L-rd": (The institution of money-release obtains) both in Eretz Yisrael and outside it.

(Devarim 15:3) "Of the gentile shall you exact": This is a positive commandment.