shrine
祏 centers on a shrine, specifically a place or object for housing ancestral tablets or sacred items.
祏 combines 示 (altar, spirit) with 石 (stone), suggesting a stone shrine or stone container for ancestral tablets.
The left side 示 represents an altar or spirit, and the right side 石 is a stone. Picture a stone shrine holding sacred tablets: 祏 is a shrine.
For セキ, imagine a sacred stone shrine where you seek (セキ) blessings: seek -> セキ, and the stone shrine is the place to seek them.