|Chapter 3: Karma-yoga|
ishtan bhogan hi vo deva
tair dattan apradayaibhyo
yo bhunkte stena eva sah
In charge of the various necessities of life, the demigods, being satisfied by the performance of yajna [sacrifice], will supply all necessities to you. But he who enjoys such gifts without offering them to the demigods in return is certainly a thief.
A distinction is made between prescribed activities and whimsical activities. One who acts per the injunctions of the scriptures will not suffer any sinful reactions since they are also following the purificatory process of acknowledging the devas or the demigods for their role in supplying these necessities. An example of this is worship of the Sun god. The Vedas enjoin every one to acknowledge their debt to the Sun god for providing sustenance to life by reciting appropriate prayers and worshipping the Sun god. One who enjoys the benefits of the Sun without acknowledging them, becomes eligible for punishment by Yamraja or the agent of death.
Ultimately all the demigods draw their potency from Lord Vishnu – which is why this process is purifying. By worshipping the demigods one indirectly acknowledges the supremacy of Lord Vishnu and thus gets elevated to a more exalted stage where in they can directly acknowledge and worship Lord Vishnu.
Srila Prabhupada comments, "The demigods are authorized supplying agents on behalf of the Supreme Personality of Godhead, Vishnu. Therefore, they must be satisfied by the performance of prescribed yajnas. In the Vedas, there are different kinds of yajnas prescribed for different kinds of demigods, but all are ultimately offered to the Supreme Personality of Godhead. For one who cannot understand what the Personality of Godhead is, sacrifice to the demigods is recommended."
Please read the Sanskrit Verse and the Prabhupada's Purport.