This Upanishad explains who is Savithri and the difference between Savitha and Savithri. It also recites the Savithri Mantra.
Who is Savitar, who is Savitri? Who is Savitar, who is Savitri? Agni is Savitar, earth is Savitri. Where there is Agni there is earth and where there is earth there is Agni. The two are causes forming one pair. Varuna alone is Savitar, water - Savitri. When there is Varuna etc., -- they are the sources, forming a pair.
Air alone is Savitar, ether is Savitri. Where there is air there is ether (and vice versa) - they are twin sources, forming a pair. Sacrifice alone is Savitar and metres are Savitri - where there is sacrifice there are metres (and vice versa). Thunder is Savitar and lightning is Savitri; where there is lightning (and vice versa). These two are twin sources. The moon is Savitar and stars are Savitri. Where there is the moon, there are the stars (and vice versa) - these two are twin sources.
Man is Savitar, woman is Savitri. Where there is a man there is a woman and vice versa. They form one pair of sources. Mind is Savitar and world is Savitri - where there is mind, there is woman (and vice versa) - these two are twin sources.
Of Savitri the first foot is Earth. 'Of that Savitar, the admirable; fire indeed is adorable, water and moon are adorable. The second foot is Bhuvar, the mind region; 'we meditate on the radiance of that deity' - the fire is the radiance; sun, moon are radiance.
The third foot is the firmament - which may inspire our thoughts - this woman and man bring forth. He who knows this Savitri conquers death. Of Bala and Atibala Virat Purusha is the seer, Gayatri the metre and deity. A, U, M are seed letters etc. Their application is to the removal of hunger etc., 'klam' etc., are the group of six limbs. Meditation: I ceaselessly practise these two, fronted by the moon pouring life into all, adept in removing sin, the rays of Vedic wisdom, whose are forms are Aum, whose bodies are solar in form!
Om, hsim bala, great goddess; hrim, mighty one; klim, yielder of four-fold human goals, granter of the boon of Savitar; hrim, adorable light of the deity!
O Atibala, embodiment of all mercy, destroyer of hunger and fatigue, we meditate on you who may inspire our thoughts. O essence of inspiration, adorned with the crown of Pranava, Hum, Phat, Svaha.
One who knows thus accomplishes his talks and shares his realm with Savitri.