Which is the best path - karma (work, action), jnana (knowledge) or a combination the two (Karma-jnana samucchaya)?A.
The stage of Karma alone is like a school in which the teaching is done with the help of inert models. The student here is completely ignorant. The statues, pictures, temples and objects in the form of past incarnations are the models through which the knowledge of the Lord is preached. Unfortunately these models are thought directly to be the Lord and are worshipped.
The second stage is the college level where the student with the knowledge of the Lord observes all the human beings as the models of the external form of the Lord, since the Lord comes in human form only. This is Pravritti in which one loves all the fellow human beings so that he will not hate the human form of the Lord whenever he recognizes. This is the actual Advaita of Adi Shankara who said that every human being is Brahman (the Lord). There is a figure of speech called 'Roopaka' or a similie [or metaphor], in which the object compared is identified with the original object. For example, this man is tiger. This means that the man and the tiger are very similar in qualities. So instead of saying that the Lord is like the human being it is said that the Lord is the human being (Jeeva is Brahman).
In the third stage of the university level, the human incarnation of the Lord is recognized and is differentiated from the other human beings by His internal form, which is His Special knowledge (Prajnanam Brahma). In this stage all the egoism and jealousy towards the human form must have been removed. At this university level, Shankara proved that He alone is Ishwara. The water in a drop and the water in the ocean are one and the same. The water is Brahman. The definition of Brahman is confined to simple awareness. In such a case every living being (Jeeva) is Brahman since every living being is having awareness. This is the qualitative similarity between the water drop and the ocean. But if you see the quantitative aspect, the water drop is the living being and the ocean is Ishwara. Shankara told not only that He is Brahman but He is also Shiva who is Ishwara (Shivo'ham). Therefore He swallowed the molten lead where as the disciples could not swallow it. Thus Shankara proved that any living being is Brahman but not Ishwara. One should not misunderstand that Brahman (qualitative) and Ishwara (quantitative) are one and the same.
Source - http://www.universal-spirituality.org/spiritualEffort.html