In the present Dark Age, the Kali Yuga application of Vedic knowledge for self realization is not necessitated. One can successfully reach state of self realization just by indulgence in spirituality contained in Bhagavad Gita. One need not refer to any other scripture of Hinduism, even Upanishads (independent spiritual treatises) to reach state of god realization.
In the present Kali Yuga the darkness of ignorance is dominating. One can cut darkness of ignorance only by indulgence in path of jnana yoga (absolute wisdom); even bhakti yoga and karma yoga would not suffice.
Even during times of Sri Ramakrishna Paramhansa, he started indulgence with spirituality contained in Bhagavad Gita via path of bhakti yoga and karma yoga alone. But finding God cannot be reached via path of bhakti yoga and karma yoga alone; he switched to path of jnana yoga.
To dissolve queries within indulgence in jnana yoga is an absolute must. The path of jnana yoga demands our indulgence in contemplation (chintan) to reach the hidden underlying meaning of sacred texts contained in scriptures of different religions of world.
None in this world in present times can understand gist of sacred texts without indulgence in contemplation (chintan), prime reason why none did so. All indulged in religious practices (path of rituals) that never led anywhere. In present Kali Yuga none can reach God following religious texts, path of rituals. Our interaction with spirituality detailed in Bhagavad Gita is an absolute must.
One single scripture Bhagavad Gita, all the 700 shlokas verses contained in Bhagavad Gita were so potential that rightly indulging in them through contemplation yields desired results.
More than anything on path of pure spirituality is the requirement of indulging in contemplation. In my 55 years of spiritual travail I still need to find a person indulging in contemplation. In 1985 I took a whirlwind tour of the world lasting 40 days just to assess the mental capability of people worldwide relating to spirituality. I returned empty-handed.
People indulged in religious practices knowing well that nothing much would be achieved doing so still, most worldwide ritually went to temples, churches and mosques to pray to god, worship him.
As per spirituality detailed in Bhagavad Gita we need not go anywhere. God Almighty all the time existed within us in miniscule form as our soul atman, the spirit existing in heart. If we are to realize self, reach God in our lifetime we have to indulge in path of jnana yoga via contemplation. Only then we can hope to reach the true inner self existing in heart.