apple of thine eye. See note on Deuteronomy 32:10.

kinswoman. The “kinswoman” here, contrasted with the “strange woman” in the next verse, is a further example of the recurring theme in Proverbs of the conflict between Wisdom and Folly.

of an harlot. Prostitution is said to be the world's oldest profession; the first reference to it in the Bible is at Genesis 34:31. It is clearly forbidden in Scripture, as are all other sexual practices outside marriage. The references in Proverbs to harlots imply that these were all “strange” women (Proverbs 7:5)—that is, “foreign” women, from pagan lands, whose very religions encouraged these vices. The Israelites had been strictly commanded not to allow their daughters to become prostitutes (Deuteronomy 23:17). Many such foreign women, even if not involved in this sin for financial reasons, had evidently become so addicted to such practices as to constitute serious temptations to those young men desiring to be faithful to God.

the goodman. This word, often translated “husband” or just “man” is translated “goodman” only here. The context perhaps implies that the relationship was that of a unmarried couple living together, rather than a true husband/wife relationship.