Conviction
Enchantment — Aura
Enchant creature
Enchanted creature gets +1/+3.
: Return this Aura to its owner's hand.
"There is no greater coward than one who believes in nothing."
John Stanko
Ultimate Masters (UMA)
• #12Rulings
Because damage remains marked on a creature until it's removed as the turn ends, nonlethal damage dealt to the enchanted creature may become lethal if you return Conviction to its owner's hand during that turn.
(wotc • 2018-12-07)
Players don't have priority to cast spells and activate abilities between combat damage being assigned and being dealt. This means that if you want to return Conviction to its owner's hand before combat damage is dealt, you must do so before combat damage is assigned (and the creature will no longer get +1/+3).
(wotc • 2018-12-07)
Rulings
Because damage remains marked on a creature until it's removed as the turn ends, nonlethal damage dealt to the enchanted creature may become lethal if you return Conviction to its owner's hand during that turn.
(wotc • 2018-12-07)
Players don't have priority to cast spells and activate abilities between combat damage being assigned and being dealt. This means that if you want to return Conviction to its owner's hand before combat damage is dealt, you must do so before combat damage is assigned (and the creature will no longer get +1/+3).
(wotc • 2018-12-07)