SB 6.1.45
yena yavan yathadharmo
dharmo veha samihitah
sa eva tat-phalam bhunkte
tatha tavad amutra vai
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
In proportion to the extent of one’s religious or irreligious actions in this life, one must enjoy or suffer the corresponding reactions of his karma in the next.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
As stated in Bhagavad-gita (14.18):
urdhvam gacchanti sattva-stha
madhye tisthanti rajasah
jaghanya-guna-vrtti-stha
adho gacchanti tamasah
Those who act in the mode of goodness are promoted to higher planetary systems to become demigods, those who act in an ordinary way and do not commit excessively sinful acts remain within this middle planetary system, and those who perform abominable sinful actions must go down to hellish life.