Bhagavadgita 17.20 onwards :
- Satvika - Danam given to the proper person at proper place and time without expecting any favor back from him.
- Proper place - holy place
- Proper time - auspicious time
- Proper person - one who is versed in Vedas
- Rajasika - Danam given expecting something in return even for fame and given with reluctance.
- Tamasika - Danam given to undeserving at improper place and improper time in an improper manner.
Bhagavdgita 17.28 : Whatever if offered , in yajna or in Danam , without faith or whatever austerity is undertaken without faith, will not yield any result - neither here nor after death.