It is said in Mahabharata that, “Sandhya means Brahma who has joined the sun. Sandhya, which is non-different from Brahma, is being worshiped by all the elements of Brahma, which are elements of the soul. I am serving such Sandhya." As divine mother is not different from such a sandhya, she is called by the name Sandhya.
'Sandhya is distinct by form. But it is the twilight that shines as the witness of karma', says Bharadhwaja Smriti.
The Agamas say that the Gayatri Mantra is composed of the fourth leg that is form of Sandhya. Therefore, the deity who should be worshiped at dawn and dusk is Sandhya.
Goddess Sandhya is said to be the daughter of Brahma in Kalikavarana.
In the Bhagavathi Purana, it is said that Sandhya, the daughter of Brahma's soul, performed penance and left her body and was born as Arundhati, the wife of Vashishtha. Sandhya is Parameswari who is the embodiment of Chichakti.
Goddess Sandhya is same as Gayatri, Savitri and Divine mother. She is worshiped during Sandhikalam. Dawn is the time before the sun rises and before the stars set. Dusk is the time after the sun set but the stars do not yet appear completely. These are twilight periods. Sandhya is meditated upon at this time. Sandhya is the dynamic energy of the Sun. This goddess should be meditated on in Ajnachakrasthana.
In Panchakosha, it is said that Manomayakosha is place of goddess Sandhya.
