G: TL;DR: Yes—action can be prayer, if prayer is understood as intention made real.

Action becomes prayer when it embodies what prayer asks for.
If prayer is alignment of will, attention, and values, then action is that alignment expressed in the world.

• Asking for compassion → acting with compassion.
• Asking for justice → doing just things.
• Asking for strength → choosing endurance when it costs something.

In that framing, prayer without action is incomplete, and action without intention is empty motion. Together, they collapse into the same thing.

行動（こうどう） は 祈（いの）り です — Action is prayer.
意図（いと） を 現実（げんじつ） に する とき、 それ は 祈り に なる — When intention becomes reality, it becomes prayer.

This definition holds whether God exists or not.