Martyr of Sands
|Creature -- Human Cleric| 1/1. 1, Reveal X white cards from your hand, Sacrifice Martyr of Sands: You gain three times X life. CSP-C [Vin Leg Ext Std legal.]
Enduring Renewal {2WW} |Enchantment| Play with your hand revealed. / If you would draw a card, reveal the top card of your library instead. If it's a creature card, put it into your graveyard. Otherwise, draw a card. / Whenever a creature is put into your graveyard from play, return it to your hand. IA-R/TSP-T [Vin Leg Ext Std legal.]
What happens:
You announce Martyr's ability and put it on the stack.
Then you choose all values for it, including X.
Then you pay the costs (1, reveal the cards, and sacrifice Martyr in any order you choose. It is irrelevant for this example. Martyr is put into the graveyard.)
The Enduring Renewal sees that Martyr died. It triggers and the trigger goes on the stack.
The stack now looks like:
Enduring Renewal returning Martyr of Sands
Martyr of Sands's ability
At that point, Martyr is in the graveyard and your "Gain 3x number of white cards revealed" is on the stack.
So, short answer, no. You can't reveal Martyr of Sands to its own ability.
