Christians: How do you go about explaining the oddness of these verses?

The idea of love being to do with your heart is a fairly modern invention. In 1st century Rome, the idea was that love came from the bowels. A thoroughly ly retentive lot, those Romans. When the Bible was translated into Latin, that's the word they used and you are reading a version of the Bible that's a poor translation of the Latin. Most modern translations from the Hebrew of Greek say "heart".