执手契约以相依白首约定成相随
[zhí shŏu qì yuē yĭ xiāng yī bái shŏu yuē dìng chéng xiāng suí]
A metaphorical expression of a couple's covenant of holding hands until old age. It highlights their mutual support and lifelong partnership, bound together as agreed at a young age. It emphasizes love enduring into senescence and fidelity in companionship.