Bhagwaan Mahaveer Evam Jain Darshan: How an abstract and spiritual be related with concrete and material

Soul is abstract and spiritual while karmic body is concrete and material. While both have different identity, both have different nature then how can they be related? How an abstract and spiritual be related with concrete and material. This question has been solved in Jain texts as follows:

Soul does not produce changes in the qualities of karma nor does karma similarly in the qualities of Soul. “Jīva does not produce changes in the qualities of karma nor does karma similarly in the qualities of jiva. The modifications of those two are the result of one conditioning the other as nimitta karana or instrumental cause”.

ण वि कुव्वदि कम्मगुणे जीवो कम्मं तहेव जीव गुणे।
अण्णोण्णणिमिनेण दु परिणामं जाण दोण्हं पि ।।
Ṇa vi kuvvadi kammaguaṇe. Jīvo kammaṁ taheva Jīva guṇe.
Aṇṇoṇṇaṇimineṇ du pariṇāṃ jāṇ doṇhaṃ pi.

(Acharya Kunda: Samayasar, 3/81)

The modifications of those two in fact, are the result of one conditioning the other as auxiliary cause or instrumental cause (निमित्त कारण). The Self is substantial cause or material cause (उपादान कारण) of his own modifications (both pure and impure); but is not the substantial cause of any of the modifications of karmic matter. The conscious mental states and neuron-physiological processes remain the substantive cause or material cause (उपादान कारण)) of changes or modifications within their own respective spheres.

Two kinds of stages of the jīva and matter are found such as: (1) intrinsic nature (svabhāva) and (2) defiled or extrinsic mode (vibhāva).

Intrinsic nature (svabhāva): 

The change which occurs in soul and matter in due course of time is intrinsic change.

Extrinsic Mode (vibhāva-parivartana):

The change which is brought in matter through effects of the soul or in soul through effects of the matter is defiled mode. The flow of the relation of soul and matter is continuously established since time immemorial. Until this relation breaks completely, the exchange of the effects remains in progress, the jīva lays its emphasis on matter and matter lays its emphasis on the jīva. The jīva in this mode or condition of being becomes the subject of feeling like attachment and aversion; as a consequence, karma binds its soul. “As conditioned by the modifications of jīva, the material particles get modified into karmas. Similarly, conditioned by the karmic materials, jīva also undergoes modifications”.

जीव परिणाम हेदुं, कम्मत्तं पोग्गला परिणमंति।
पोंग्गल कम्मणिमित्तं, तहेव जीवो वि परिणमदि।।
Jīva pariṇāma heduṁ, kammattaṁ poggalā pariṇamanti.
Poṇggala kammaṇimittaṁ, taheva jīvo vi pariṇamadi.

(Acharya Kunda: Samayasar, 3/80)