clamar en el desierto

1.
Pan-Hispanicfigurativeneutral
- To make appeals, warnings, or statements that go unheard or unheeded; to expend effort in vain because the intended audience does not respond.
- To speak or act fruitlessly, as if addressing an empty or indifferent space.
2.
Pan-Hispanicliteralreligiousliterary
- To cry out in an actual desert or deserted place, often evoking biblical or solitary imagery.

Examples:

ES: Veo que esta sala está llena de prejuicios, y que levantar la voz aquí es como clamar en el desierto.
EN: I realize that this hall is charged with prejudice And to raise my voice here is to cry out in the wilderness.
ES: Al fin logramos nuestro fin, Roon, tras esperar 18 años... tras clamar en el desierto, y tras la reforma militar
EN: We've finally reached our goal, Roon, after waiting for 18 years... after preaching to deaf ears, and after rebuilding the army with you.
ES: No clamar en el desierto.
EN: Not pushing on the ocean.
ES: Tengo la impresión de clamar en el desierto.
EN: Is it always like that? It felt like talking to a wall.