B.G 4.12

काङ्क्षन्तः कर्मणां सिद्धिं यजन्त इह देवताः। क्षिप्रं हि मानुषे लोके सिद्धिर्भवति कर्मजा ॥१२॥

kāṅkṣantaḥ karmaṇāṁ siddhiṁ yajanta iha dēvatāḥ। kṣipraṁ hi mānuṣē lōkē siddhirbhavati karmajā ॥12॥

[काङ्क्षन्तः कर्मणां सिद्धिं यजन्त इह देवताः। क्षिप्रं हि मानुषे लोके सिद्धिः भवति कर्मजा॥
kāṅkṣantaḥ = to desire; karmaṇāṁ = prescribed action; siddhiṁ = accomplishment/success; yajanta = they sacrifice; iha = in this world; dēvatāḥ = to (other) gods;। kṣipraṁ = quickly; hi = certainly; mānuṣē lōkē = in the human world; siddhiḥ = accomplishments; bhavati = are obtained; karmajā = from the prescribed duties;]

Desiring early success for their actions in this world, they sacrifice to other gods. Certainly, they obtain fruition quickly in the human world by the prescribed duties.

Gīta Bhāshya 4.12

The results are obtained faster by performing prescribed duties and offering it to the lord who is present within other deities.

कुतो मम वर्त्म अनुवर्तन्ते - क्षिप्रं हि। अत एव हि फलप्राप्तिः।

kutō mama vartma anuvartantē - kṣipraṁ hi। ata ēva hi phalaprāptiḥ।

[kutō = why indeed; mama = my; vartma = way / behaviour; anuvartantē = follow along; - kṣipraṁ hi = "kṣipraṁ hi" i.e. "quickly indeed" । ata ēva = because of this only; hi = indeed; phalaprāptiḥ = results are obtained;।]

Why indeed, it is said - "mama vartma anuvartantē", i.e. "they behave subservient to Me" (4.11)? Is explained by the verse "kṣipraṁ hi" i.e. "quickly indeed" (because they obtain results quickly).

"तस्मात्ते धनसनयः"

इति श्रुतिः ॥१२॥

"tasmāttē dhanasanayaḥ"

iti śrutiḥ ॥12॥

[tasmāttē = therefore, they; dhanasanayaḥ = accumulate wealth;]

[iti śrutiḥ = states Vedic testimonial.]

"(Those who play music in front of the King, play for You who is present within the King, and) Therefore they accumulate wealth."

- states Vedic testimonial (from Chāndogya Upanishad).