Historical Rules · 13 October 2023
Rule 118.3
Official source text from the 13 October 2023 Rules release
A player can’t pay a cost without having the necessary resources to pay it fully. For example, a player with only 1 life can’t pay a cost of 2 life, and a permanent that’s already tapped can’t be tapped to pay a cost. See rule 202, “Mana Cost and Color,” and rule 602, “Activating Activated Abilities.”