When and how did they see God? They saw God when they were in the state of deep meditation (samadhi)! There is nothing like seeing God physically with eyes open! What happened was- they realized the bliss that is known as God.

As for seeing God- we all know that Arjuna could see the Vishwaroopa- the Lord’s cosmic form only when the power to see the cosmic form was specially bestowed upon him by Krishna.

(Bhaktimala Jan 1977)