In the scriptures of Hindu religion (Sanatan Dharm), the way of worship mentioned in the Vedas and the Gita is correct for going up to Heaven and (Mahaswarg) Great Heaven, but it does not lead to complete salvation. Due to which, the cycle of birth and death of the worshipper continues. The spiritual practice mentioned in the Vedas and the Gita is the same because the Shrimad Bhagavad Gita contains the same knowledge as that of the Vedas, in brief.
Majority of the Hindus perform Pitra (manes) worship and ghost worship only. They also worship the deities (Shiv ji and Vishnu ji). In Gita Chapter 9 Verse 25, the Lord, who has given the knowledge of Gita, has clarified that those, who worship Pitras, attain the life of a Pitra (mane) and go to Pitra Lok. Those who worship ghosts (phantoms) become ghosts and live among them. Some live in Shiv Lok who are the worshippers of Shiv. There is a Pitra Lok in every deity’s Lok (world). Ghosts, ganas (attendants) and the Pitras (manes) reside in it. Then, it has been stated in this same verse (9/25) of Gita that those who worship the deities go to the same deity's (Lok) world. There also they reside in the Pitra Lok. A Pitra Lok is like the residence of the servants away from the bungalows of the officers. The facilities which are available to the officers are not available to the servants. Likewise, the facilities that the main deity enjoys in heaven are not available to the (Pitras) manes. The Knowledge-giver of Gita has further mentioned in this very verse (9/25) of Gita that those, who worship me (Kaal Brahm), attain me i.e., they go to Brahmlok. It has been clarified in Gita Chapter 8 Verse 16 that those who go to Brahmlok (the great heaven of Kaal), have to come back to earth from there. Even their cycle of birth and death never ends.
In Gita Chapter 3 Verses 10-15, there is recommendation for doing Yagya. Yagya means religious ritual. There are five main religious rituals: - 1. Dharm Yagya, 2. Dhyaan Yagya, 3. Havan Yagya, 4. Pranaam Yagya, 5. Gyan Yagya. In the scriptures, the description on the performance of Yagyas is as follows: -
First of all, initiation is taken from a Guru. Then it is beneficial to perform Yagya (religious ritual) by the order of that Guru ji as per his guidelines.
If only the above yagyas (religious rituals) are performed, then that worshipper gets the comforts of heaven (Jannat) for some time according to his rituals. After enjoying the comforts in the heaven, one has to also bear the punishment of one’s sinful deeds in hell (Jahannam). There are some sins whose punishment one has to bear on the earth in the lives of animals, birds, insects etc. One can also get a human body. If one has done a lot of yagyas, then one also becomes a king. But the cycle of birth and death can never end. The duration of heaven and kingdom is very short.
If the true (naam) mantra is also chanted along with these yagyas (religious rituals), then the fruit one gets is more and better.
In Yajurved Chapter 40 Mantra 15, it has been prescribed to chant Om (ॐ) (naam) mantra. Gita is the essence of the Vedas. In Gita also, in Chapter 8 Verse 13, it has been mentioned to chant Om (ॐ) naam. The Vedas and the Gita prescribe recitation of Om naam and performance of the spiritual practice of the above-mentioned yagyas (religious rituals).
Important: If a person, who chants Om (ॐ) mantra along with the yagyas religious rituals), dies while doing this spiritual practice throughout his life, he attains Mahaswarg (Great Heaven) i.e., Brahmlok. He enjoys comforts for a longer duration. But he would have to suffer in the hell (Jahannam) too, and the cycle of birth and death will continue forever. One has to also suffer in the bodies of animals, birds and other creatures.