The word sva-tantra means freedom. In sri vidhya upasana the term tantra more refers to ones own style or the way. “Sva” means self, tantra means the way, hence the namavali means to follow ones own way.
why is it an emphasis to follow one’s way in a ritual scripture ?
In the context of sri vidhya freedom is of great importance. Freedom from what ?, Freedom from the conclusions in our life. Tantra in sri vidhya context is ever evolving. Though we see the sun rise and set daily, though we experience all the climates each year, it is never same as the previous day or year. This ever evolving dynamic factor is represented and worshipped as shakthi. That which transforms everything in one way or another is revered as shakthi in Sri Vidhya Upasana. In short Sri Vidhya upasana can also be viewed as an art of dynamics. This sense of dynamics over objects and elements of the nature applies also to our life, hence one should develop the skill to move through the dynamics without being too influenced by the conclusions derived from the experiences. May be the same instance again will not have the same impact and effect. This state of not being deluded by the conclusions is actually termed as “Sva-Tantra” or freedom in the context.
How is it connected to Devi ?
She is the one who can bestow that strength to attain this state is the meaning of namavali. As previously explained, dynamic which causes everything to transform is what is needed in everyones heart. To put it in the simple perspective, a ball thrown while running to an another running person is just a passing, if the same is done if any one is standing then the ball hits the static person. It is a reverential hymn of devi praying an equally dynamic self to withstand and uphold to the pace of life.