Lending is fine to brethren without interest. The problem He had in the Temple was that people were charging abhorrent interest, making it very difficult on the people.

Luke 6:34-35
And if you lend to those from whom you expect to receive, what credit is that to you? Even sinners lend to sinners, to get back the same amount. But love your enemies, and do good, and lend, expecting nothing in return, and your reward will be great, and you will be sons of the Most High, for he is kind to the ungrateful and the evil.