Bhashya :- eyes like Moon and the Sun should be understood as in the case of I am the sacrifice (as originating from Him). This would then be according to Rigvedic statement – “Since all the gods having been produced from his parts, they and the seers are praised as the parts of the Lord”. Similarly, “From the mind the Moon was born, from the eyes the Sun was born”. In view of the multitude of forms, it is proper that in the multitude of forms shelter is said to have been taken.”.
20. The space between heaven and the earth along with all the quarters is filled by You alone. Seeing this terrible form or Yours, the three worlds tremble, O Exalted One!
Bhashya :- Between the mother (Earth) and the father (Heaven) He is the One alone, thus in Varuna scripture. Singly, He has enveloped the space in between earth and the heaven. The words, behold, O Partha, My forms clarify Arjuna's intention to see his innumerable forms. The mother and father are the earth and the heaven - “Let mother earth not encourage me towards bad deeds”, “Let the heaven, my father be propitious to me”, due to such usages. His form is not normally of fearsome form. For Narada and others that form is not fearful. For some, the Lord shows His frightful form. “While some find fulfillment seeing His form, others become frightened. But seeing it repeatedly all find fulfillment”, thus in Varuna section. All cannot see that form of the Lord. Others in the course of meditation seeing His terrible form are frightened. “Seeing the universal form of the Lord and being pleased thereby, the frightened aspirants who, even though they have not seen Him, meditate on Him with their mind, eyes and other senses concentrated and feel as if they have perceived Him” - thus in Gautam section.