Karika 13

सत्त्वं लघु प्रकाशकमिष्टमुपष्टम्भकं चलं च रजः। गुरु वरणकमेव तमः प्रदीपवच्चार्थतो वृत्तिः ॥१३॥

sattvaṁ laghu prakāśakamiṣṭamupaṣṭambhakaṁ calaṁ ca rajaḥ। guru varaṇakamēva tamaḥ pradīpavaccārthatō vr̥ttiḥ ॥13॥

[सत्त्वं लघु प्रकाशकम् इष्टम् उपष्टम्भकं चलं च रजः। गुरु वरणकम् एव तमः प्रदीपवत् च अर्थतो वृत्तिः॥
sattvaṁ = the satwa is; laghu = light; prakāśakam = bright; iṣṭam = desirable; upaṣṭambhakaṁ = exciting; calaṁ = moving; ca = and; rajaḥ = is the rajas; guru = heavy; varaṇakam = enveloping; ēva = that only is; tamaḥ = the tamas; pradīpavat = they illuminate like a lamp; ca = and; arthatō = give purpose; vr̥ttiḥ = to mental activities/ volitions;]

The 'satva' is light, bright, and desirable. Exciting and swiftly moving is the 'rajas'. That only is the 'tamas' which is heavy and enveloping. These qualities illuminate like a lamp and give purpose to the volitions.

'vr̥ttiḥ' is mental act before it manifests in physical form. We will use 'volition' or 'mental act' as an equivalent translation. Important to differentiate between 'vr̥ttiḥ', a mental act and 'karma', a physical act.]