The soles of His lotus feet have various divine impressions like that of the chakra, the disc, lotus and so on. According to the Vishnu Purana there are fifteen such auspicious markings, whose secret only Shri Krishna knows. Various Vaishnava spiritual masters have explained the meanings of these markings in different ways, but no one knows the real meaning accept Shri Krishna Himself. A devotee should not get caught up in all these useless discussions. He should just remain absorbed in the loving remembrance of Shri Krishna's names, forms, pastimes, virtues and so on, and desire His eternal divine service. Then he will naturally desire to remain a million miles away from knowledge related to God's almightiness.
Just think, two men went to a mango orchard. The first man asked for a mango, ate it and left. The second man, using logic and arguments, started asking the gardener, "Whose orchard is this? How many years has it been here? How was this tree planted? Did the tree come from the seed or the seed from the tree? Did the seed come first or the tree?" While engaging in these arguments, he suddenly died. Without even tasting a mango he left this world, and that too, without coming to any conclusion.
Therefore, true Rasika Saints do not get involved in these useless discussions. They consider Shri Krishna to be either equal or even less than themselves. But, it is only the sentiment of adoration and love that pervades all their relationships with Shri Krishna.
Jagadguru Shri Kripalu Ji Maharaj
An excerpt from Rupadhyana - Loving Remembrance, the English translation of Rupadhyana, p. 49