Here are my notes from reading Proverbs 9.
Wisdom is building a house and preparing (v.1-3).
She calls to those who are naive and lack understanding to come to her house (v.4-5).
Forsake folly and live and proceed in the way of understanding (v.6).
He who corrects a scoffer gets dishonor for himself and he who reproves a wicked man gets insults for himself. Don't reprove a scoffer or he will hate you. A scoffer and/or a wicked person will not receive criticism. They will be angry and turn against the person who is trying to help them. Reprove a wise person on the other hand and that person will love you (v.7-8).
Give instruction to a wise person and they will become wiser. Teach a righteous person and he will listen and increase his learning. He will understand that he needs to learn more and that they do not know everything. They should listen and understand and know that there is always going to be someone smarter, wiser, more mature than them, and therefore have more experience in that are that is being taught to them. Therefore they should also show their teachers respect (v.9).
The theme of the Book of Proverbs is reiterated here. "The fear of the Lord is the beginning of wisdom, and the knowledge of the Holy One is understanding" (v.10).
By me your days will be multiplied and years of life will be added to you. This only happens if you are the wise person (v.11).
If you are wise, you are wise for yourself and if you scoff you alone will bear it. You can either choose to be wise and reap the benefits of doing so or you can scoff and incur the penalty (v.12).
Women of folly is described as:
Knows nothing (v.13)
She calls to those who are making their paths straight- those who are going straight on their ways, not staying off the path, those who are living in an upright manner, righteous person, wise and pleasing to God. (v.13)
Calling all those who are naive and lacking understanding to turn aside for a moment to her place. (v.16)
Stolen water is sweet and bread eaten in secret is pleasant. This reminds me of the saying "What somebody doesn't knows can't hurt them." Even though when it is found out as seen in the previous chapter there is nothing they can do about it, they cannot give it back. (v.17)
The naive will not know or realize that the dead are there and that the woman of folly's guests are in the depths of Sheol are there. He won't find out until it is too later and he has already been a participant in the act/crime. (v.18)
This act/crime can be anything, not just adultery.
This is what I got from reading Proverbs 9.