The three main philosophies of Vedanta are Sankara’s Advaita, Ramanuja’s Visistadvaita, and Madhva’s Dvaita, all these three claim to be pure and pious texts, but each of the three saints explains the ways of attaining salvation in a different manner.
Advaita philosophy states that the blessed souls would easily merge with the Lord, and they cannot take re-births again. According the Advaita, there is no difference between Lord Shiva and his creations, provided if the creations live their life in a pure and pious manner, and considers Lord Shiva as the supreme god.
The Dvaita philosophy tells that lot of difference exists between the ordinary souls of the people and the almighty, and as per the teachings of Madhwacharya, Lord Vishnu is the supreme god, and all of them are his divine attendants only, and according to him, merging with the almighty is almost impossible. But by sincerely worshipping Lord Hari, there is a possibility for his devotees to reach the divine worlds and to stay there for a long time, but at the same time, they cannot be merged with the god.
According to Ramanuja’s Visistadvaita, if a person surrenders himself on the feet of the god fully, then there is a possibility in attaining salvation after his death. But Ramanuja ask us to worship a holy spiritual guru, before worshipping the almighty in order to get the eternal bliss. He considers that all the living beings contain the features of Lord Vishnu.
These three Hindu saints were very good natured and holy, and they act as an example for others. Though their philosophies differ from each other, but their ultimate goal is make the people to show their sincere devotion on the almighty.
According to my opinion, at this present Kali Yuga, merging with the god is almost impossible, since whether knowingly or unknowingly we are committing lot of sins in our life regularly. But at least we can try our level best to do good things in our life, and also pray to the almighty to give salvation to us.