This excerpt from the Matsya Purana describes the Tula Purusha Dana, where a king would weigh himself on a giant scale and then donate an equal amount of gold to the Brahmanas. In the process of doing so, the king is supposed to utter the following verses to the scale:
[Y]ou are the strength of all the Devas and rest on truth. I salute you, O Jagaddhatri! you have been designed by the Lord Brahma as the witness. You hold yourself between the Truth and the Untruth. You are the life between the Virtuous and Vicious. You weigh all. Weigh me then, and carry me across the ocean of the world. I salute you. Only in you is the Lord of the twenty-five elements inherent. I therefore salute you. I salute you, O Govinda! in the form of this scale. O Hari! be gracious enough to see me taken across this ocean of the world.
My question is, why does it say "you have been designed by the Lord Brahma as the witness?" Are there any other scriptures which describe Brahma creating a scale?
Also, why is the scale praised as a form of Vishnu, and why does it say "[o]nly in you is the Lord of the twenty-five elements inherent"? For those who don't know, the Samkhya school of philosophy posits 24 elements which arise from Prakriti, as well as a 25th element called Purusha. The Yoga school goes one step further and posits the existence of an Ishwara or Lord, as I discuss in my question here. But why would the Matsya Purana say that Ishwara is only present in the scale?
Is the scale supposed to be symbolize something? In Greek mythology the goddess of Justice holds a scale in her hand, symbolizing the impartiality of justice. Is something similar going on here?