The Vedic Tradition in
Goddess Saraswathi represents the ideal Guru, sitting on a lotus holding the sacred scriptures in one hand and a mala in the second hand. With the other 2 hands she plays the Veena
Holding the Scriptures - indicates that she upholds the knowledge of the scriptures which alone can lead to the truth.
The 4 Hands - represents the 4 aspects of the inner personality - Manas (mind), Buddhi (intellect), Chitta (conditioned consciousness, memory) and Ahamkara (ego).
The Veena - The suggestion is that the guru tunes up the mind and intellect of the seeker to be in perfect harmony with the universe, and thus he surrenders his individual conditioning and ego.
Source: Excerpt from an article published in the magazine October 2000 edition of Chinmayam a magazine of Chinmayamission.