Commits should be long and detailed, though the details for the commit log are for a different purpose. In the commit logs I want to know why the change was dev

Commits should be long and detailed, though the details for the commit log are for a different purpose. In the commit logs I want to know why the change was developed -- what issue it fixed, what feature request it implements. I want the code comments to explain the logic of a large chunk of code, at a higher level than just reading line by line.