Need help understanding this

Question

I am reading up on the jhana and theres this paragraphs. There talking about the 3 ways Beginning, Middle & End and the 10 characteristic of jhana. I'm not sure what im suppose to do or what this is suppose to mean. The book is the path to purification.

“‘Of the first jhána intensification of equanimity is the middle’: how many characteristics has the middle? The middle has three characteristics. He [now] looks on with equanimity at the mind that is purified; he looks on with equanimity at it as having made way for serenity; he looks on with equanimity at the appearance of unity.32 And in that he [now] looks on with equanimity at the mind that is purified and looks on with equanimity at it as having made way for serenity and looks on with equanimity at the appearance of unity, that intensification of equanimity is the middle of the first jhána. These are the three characteristics of the middle. Hence it is said: ‘The first jhána is good in the middle which possesses three characteristics.’

Heres the full page. The parts specifically im asking about is on line 112

Answer 1

My reading of the text finds there is only one practise to perform, namely, looking on with equanimity. The other characteristics, such as serenity, unity, etc, occur automatically when the mind automatically manifests jhana from the practice of developing equanimity.

The Pali scriptures (SN 48.10) teach jhana is developed by making 'letting go' the meditation object. The text in question is stating when the mind jhana becomes serene or has rapture, etc, to look upon those features & characteristics with equanimity. In other worlds, don't cling to those characteristics & features.

And what is the faculty of concentration? There is the case where a monk, a disciple of the noble ones, making it his object to let go (vossagga), attains concentration, attains singleness of mind. Quite withdrawn from sensuality, withdrawn from unskillful mental qualities, he enters & remains in the first jhana... SN 48.10

Answer 2

That is an effect of dasavidhaappanākosallaṃ, that appear before your quote.

My link is just a head. There is more information in that book after the head.

For a guideline:

Beginning = complete and perfect practicing of all dasavidhaappanākosallaṃ (achieved jhāna).

Middle = an effect of the 7th of dasavidhaappanākosallaṃ.

End = an effect of the 6th of dasavidhaappanākosallaṃ.

You must memorize dasavidhaappanākosallaṃ head, and meditate it to get a deep understanding.

Note: I never read throughout the english translation version (my english is terrible), that make me not sure about the translation's quality. So you can ask more, if you see something that is unclear.