In brief
The rock relief and Buddhist images form a common spatial ensemble.
Useful to know
The Longmen Caves in China house Buddhist sculptures and niches associated with the North Wei and Tang periods. UNESCO sees them as an important ensemble of stone religious sculpture. [1]
When looking at a separate statue, include in the observation its niche. The size of the opening, the surrounding rock surface and the adjacent images change its perception. It's not just a sculpture set in a random hall. When comparing parts of the ensemble, check the period and the specific place; the common name of the object does not mean that all the figures were created simultaneously.
Sources
For further detail and to check the information: