Wúlùn yùdào shénme kùnnan, tā de xìnniàn dōu jiānrú-pánshí.
No matter what difficulties he faces, his convictions remain rock-solid.
Tips
history
Echoes the Han-dynasty Yuefu ballad 《孔雀东南飞》: 磐石方且厚，可以卒千年 - the rock is square and thick, lasting a thousand years. 磐石 has stood for permanence in Chinese poetry ever since.
usage
Used for abstract things that should not waver: friendship, faith, alliance, foundation, position. For physical strength of buildings, prefer 固若金汤.
