Ramanujacharya maintained that the wisdom of the Shrutis points to the fact that Shiva and Jiva (Universal Soul (God) and the individual soul) are not same, although they are not separate from each other. While universe is the body of Brahman, He is the Soul and controlling Power of the universe.
Brahman is not only the material and efficient cause of the universe; He has in fact become this universe of multiple names and forms. God has become all, even though remaining separate from His creation. It is not illusion or Maya.
God is seen as having all the benevolent qualities (Grace, Compassion, bestowing blessings etc.) and also the power to create, maintain, and destroy the creation. The highest ideal, and the final goal of human endeavor, is to love and worship God as our own, and completely surrender oneself to Him.
Thus, Ramanuja's philosophy is called Advaita nondualism with qualification - as it accepts the plurality both of matter and of souls. Vishishtha Advaita or qualified monism of Ramanuja is a philosophy of love and devotion; we can say he propounded Bhakti Yoga as the path to reach the Truth.
Therefore it gives a synthetic view of the spiritual experiences of God or Brahman. Heavily depending upon theory of Karma, this philosophy applies the law of cause and effect to moral experiences. It brings to light the inner working of righteousness of God and affirms the impossibility of cruelty and bias in Divine nature.
As you sow, so would you reap! This law applies to explain suffering for many and comfort for others. But the Grace of God, the most benevolent being, transfigures the rigorous law of karma and thus His grace or 'kripa' becomes the ruling principle of religion.
Thus Ramanuja added concepts of devotion, worship, and faith as new dimensions to Vedanta. Ramanuja does not accept the impersonal and 'attributeless' Brahman of Shankara, but rather an eternal personal Brahman, the repository of all blessed qualities.
Qualified non-dualists believe that God is the cause and the universe its effect, but as the effect can't be different from the cause, God is immanent in whole universe. Like the spider, God projects the whole universe from within Himself and therefore can withdraw it in Himself. Similarly, God can reach anywhere, as the spider reaches anywhere in the web.
As from the blazing fire, fly millions of sparks of the same nature; even so from this Infinite Being -God- these souls have come. Instead of Maya, here we can say, that Ramanujacharya posits creative Power or Shakti of God.
The main theme is that it is Brahman Itself who has become this whole universe. Thus Ramanuja accepts the reality of cosmos/universe/world as the manifestation of Brahman, differing here with Maya theory of Shankara.
Here it must be made clear that Shankaracharya did not reject the manifest world as non-existent, but he called it 'relatively real' and not absolutely real. This concept is based on the differing definitions of knowledge given by Shankara and Ramanuja.
Shankara is strong proponent of Jnana Yoga. Final Liberation comes when the knowledge of unity of individual soul and eternal Soul is established through discrimination and dawning of universal intuition, transcendental oneness with Knowledge.
The difference also alludes to one of the controversial aspects of interpretation of scriptures as far as relation between karma and knowledge is concerned. For Acharya Shankara the Highest Knowledge and the karma are antithetical to one another, while others, like Ramanujacharya and Vallabhacharya appear to disagree with him.
Shankaracharya insists that the knower of Brahman, Brahmajnani, is free from all karma, both in their aspects of the effect on and the necessity for the realized soul. "Ramanuja, on the other hand, does not take into consideration knowledge that is self-luminous and absolute.
Knowledge, he declares, is always relative, and in it there is always a distinction between subject and object. In short, Ramanuja does not admit nirvikalpa samadhi, the unitary consciousness, the experience of the Self as one with Brahman."
For Ramanuja savikalpa samadhi is the highest transcendental experience that the Jiva can have.
His Vedanta also emphasizes the pre-requisites such as 1) approaching the Guru with due humility, who is established in the Knowledge of Brahman, and learning from him that vidya, 2) giving up all attachments to this world and the next, and 3) Grace of the Lord to attain to the transcendental knowledge, in addition to the scriptural studies and sadhana.