So those who are not able to perform the cent per cent progress, they have to remain in the material world, but according to the percentage of progress, they are allowed to take their next birth either in a rich family or in a very pure family; in both the cases, one is given the chance to have human form of life so that one can make progress from the point where he ended in his last life. The best thing is that every intelligent man must try to finish this business of Krishna Consciousness in this life. Finishing means one has to conclude that he has no more any necessity for material enjoyment. Spiritual enjoyment of life is the reality, and when one is perfectly prepared to accept spiritual enjoyment, and completely understands the uselessness of material enjoyment, that is the perfectional point of view.
Letter to Aniruddha, 24 August, 1969