Ritual of Rejuvenation
This is the kind of card a common slot exists to fill: a small life buffer stapled to a cantrip, priced so the card replacement is the part you actually pay for. The four life is the sweetener, not the point. White has a long tradition of these life-and-draw instants at the low end of the curve, and they all live or die on the same arithmetic: three mana to draw one card is a poor exchange in any deck that wants to win, so the lifegain has to carry the rest of the cost. That makes it a defensive stabilizer first. You hold it through a race, blunt a turn of incoming damage, and refill your hand in the same breath, all at instant speed so nothing about your tempo commits early. Nothing here scales, nothing builds toward a payoff, and the card asks for no deckbuilding around it. It is fixed-rate insurance for decks that expect to be under pressure and can afford to spend a turn not advancing the board. Where lifegain itself is a resource (drain-and-payoff shells, life-total-matters builds), the gain becomes a small enabler rather than a wash, but the card was never engineered for that synergy; it simply happens to feed it.
