The service of love and devotion offered to God is the true passport to the spiritual world.
Krishna, God says, "Only by devotional service, and only thus, can one know Me as I am. And the being who, by such devotion becomes fully aware of My Person, can then enter My absolute kingdom."
It is now, during our present life, that we must prepare our next existence, and thus our entry into the absolute kingdom of God. To achieve this we must surrender ourselves to Krishna, and serve him with love and devotion. By engaging our whole being in the absolute devotional service of the Lord, we receive our true passport to the spiritual world as soon as we leave our present carnal envelope. With the beginning of the devotional service offered to the Lord begins the spiritualization of our present body, so that as a pure being we no longer find any reason to be in a body of dense matter.
The Lord explains Himself in the Bhagavad-gītā (Words of Krishna, Christ, God, the Supreme Person), concerning his appearance and his disappearance, that he who perceives its true nature, spiritual and absolute, and who knows them to be the effect of its inconceivable power, is liberated from the laws that govern birth and death. He then reaches the spiritual world, inhabited by the eternal Vaikuṇṭhas planets, where the liberated souls live forever, far from the clutches of birth, sickness, old age and death. There, the Lord and all who are eternally absorbed in the service of absolute love offered to his Person, enjoy an eternal youth, because there is no old age, no disease, no death. And because death is absent, so is birth. We must therefore conclude that the mere fact of understanding in their truth the appearance and the disappearance of the Lord makes it possible to attain the perfection of eternal life.
In the Lord lies truthfulness (truthful, true, real character), purity, intolerance to the misfortune of others, control of anger, inner satisfaction, integrity, mental equilibrium , mastery of the senses, sense of responsibility, equality of soul, tolerance, equanimity, loyalty, knowledge, detachment from sensual pleasures, the power to govern, valiantness, influence, ability to make everything possible, fulfillment of just duty, total independence, dexterity, perfect beauty, serenity, benevolence, ingenuity, kindness, magnanimity, determination, omniscience, rightness in action, possession of all objects of pleasure, joy, immutability, fidelity, fame, universal adoration, humility, divinity, eternity, and a thousand other spiritual attributes, all eternally present in Him, and of whom He did not never miss.