To me, it appears to overcome the five hindrances is needed for jhana. The sutta say:
- quite secluded from sensual pleasures, secluded from unskillful qualities, they enter and remain in the first absorption
The suttas do not say:
- they enter and remain in the first absorption, thus become quite secluded from sensual pleasures, secluded from unskillful qualities.
Sutta such as MN 38 literally say the mind is purified from the five hindrances prior to jhana.
The vipassana contemplations of the Satipatthana Sutta (MN 10) are fake dhamma; composed by intellectuals; similar to how the Abhidhamma about fleeting mind moments at 1/billionth of a second was concocted by intellectuals. While in true Satipatthana there is obviously vipassana regarding the not-self, unsatisfactory & impermanent nature of body, feelings & mind; this vipassana is not a constant "flashing" or arising & passing of momentary objects (unless step 13 of Anapanasati is reached).
"Vipassana" itself literally means "clear seeing" therefore it cannot be vitakka & vicara because "seeing" is not "thinking".
Vitakka & vicara in the 1st jhana do not refer to ordinary thinking. They refer to the mind very subtly moving towards & exploring the other factors of jhana. Ajahn Buddhadasa and later Ajahn Brahm have explained this. There is no ordinary thinking in the 1st jhana. There are no habitual jhana preachers on the internet who have actually attained any jhana. MN 19 clearly literally says the Buddha made the mind quiet well before the 1st jhana.
Sujato's translations appear to contradict his previous writings, such as Why vitakka doesn’t mean ‘thinking’ in jhana. Vitakka & vicara in the 1st jhana do not mean placing the mind & keeping it connected. Here, in Sujato's sutta translations for kindergarten students, Sujato is also contradicting his own teacher Ajahn Brahm and has adopted a translation that is Visuddhimagga and thus not Early Buddhism.
In summary, apart from seeing clearly the impermanent subtle changing intensity vibrations of rapture, the primary vipassana occuring in the 1st jhana are:
seeing clearly the disturbing/unsatisfactory nature of rapture; how rapture is inferior to the peace/stillness of letting go
seeing the not-self/alien nature of rapture & jhana.
seeing the emptiness of self because self-view has dissolved.
In summary, the type of rapid arising & passing described in MN 10 is not occuring in the 1st jhana or any jhana because all jhanas are "ekaggata".