You may wish to check out Ven Analayo's outstanding work "Satipatthana: the direct route to realization". In it, he does a good job at explaining why first jhana is not a pre-requisite for sotapatti-magga and sakadagamita-magga.
Within my own (sub) tradition, we practice the samatha-variant of ananapa-sati for one third of a retreat's duration. During that period, we are encouraged to develop moment to moment concentration and access concentration. When one is well established in insight practice, one is encouraged to develop jhana before returning to vipassana.
“No lists of things to be done. The day providential to itself. The hour. There is no later. This is later. All things of grace and beauty such that one holds them to one's heart have a common provenance in pain. Their birth in grief and ashes.”
- Cormac McCarthy, The Road
Learn this from the waters:
in mountain clefts and chasms,
loud gush the streamlets,
but great rivers flow silently.
- Sutta Nipata 3.725
(Buddhist aid in Myanmar) • •
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