Yoga Sūtra Chapter Four verse 9

जाति देश काल व्यवहितानामप्यान्तर्यां स्मृतिसंस्कारयोः एकरूपत्वात् ॥९॥

jāti-deṣa-kāla-vyavahitānām-api-ānantaryaṃ smṛti-saṃskārayoḥ eka-rūpatvāt ||9||

Even though separated by existence, place and time,
there is a succession because memory and tendencies
are of one form.

jāti - the form of existence, existence; birth, production; re-birth; position assigned by birth, rank, caste, family, race, lineage; genusdeśa - place, point, region, spotkāla - time, a period of time; season, the proper time or season forvyavahita - screened from view, concealed, covered; separated, not contiguous or immediately connectedapi - even, also, although; very; something more; moreoverānantarya - immediate sequence or succession; proximity, absence of intervalsmṛti - remembrance; memory; mindfulness; the whole body of sacred tradition or what is remembered by human teachers and constantly revisedsaṃskāra - tendencies, psychological imprint, mental impression, habitual potency; making sacred, hallowing, consecration, making ready, preparation; a sacred or sanctifying ceremonyeka - one; alone, solitary, single, happening only once, that one onlyrūpatva - character; the state of having form or figure

Commentaries and Reflections

Commentary by TKV Desikachar:

Saṃskāra is so powerful,
it can lead you to act without thinking.”

“But Saṃskāra can be fed by Vāsanā.”

“When I do something is it
because I want to do it,
or am I being led to
do it by the mind?”

Commentary by S Ramaswami:

“Unless you introduce the idea of Vāsanā, how can you justify Karma?How does it act?
Even though each life is separated by place, time and space, the cycle is endless.
All these things do not prevent the Vāsanā from operating again.
Saṃskāra is the Citta or Citta is the remainder of Saṃskāra or Vāsanā.
Smṛti is a Cittavṛitti.
It is only when Saṃskāra or Vāsanā manifest themselves in Smṛti that you know it.
In this birth only those Saṃskāra pertaining to human birth come out.
Thus you carry around all the Saṃskāra of our endlessness.
Thus Vāsanā are Karma Āśaya or the remainder of activities. Specifically, Karma Āśaya are the latent impressions of deeds which produce results afterwards; while the latent impression of feelings created by going through the three-fold experience of birth, life-span and pleasure and pain is called Vāsanā or affective imprint on the subconscious.
Thus it is said that Karma Āśaya or latent impression of action manifests the appropriate Vāsanā. From that, arises clear memory. Karma Āśaya is the unfailing cause of memory. Thus, from latency arises memory and from memory latency is formed; and so the cycle goes on.
Thus Vāsanā are these that allow you to take a particular Janma and these that continue to allow you to operate in this one.”

Commentary by Paul Harvey:

Saṃskāra always looks
to our past experiences
to determine our choices
for our future actions.”