Vidura looks like a human being; "self-same body" means looking like material body. Any devotee always is in a spiritual body although it may appear material; Smoke is smoke; When Krishna says unto me, he means unto "me." So he should not be pictured with Radharani,* Why a snake? Being entangled in the qualities of material nature is very subtle, so why a snake?
Self-same body means
Correspondence
1971 Correspondence
Vidura looks like a human being; "self-same body" means looking like material body.
Letter to Jadurani -- Calcutta 19 May, 1971: