12 people were killed and 58 were injured when a gunman opened fire at a midnight screening of The Dark Knight Rises in Aurora, Colorado on July 20.
Bale, who starred as Bruce Wayne/Batman in The Dark Knight Rises, recently visited some of the victims recovering from their injuries in a local hospital without encouragement from Warner Bros and media.
Speaking on The View, Lambert said: "As an entertainer myself, I feel like it makes me want to go do something nice.
"It wasn't in the press. It was just out of the kindness of his heart. It's really cool he didn't do it for attention."
Hans Zimmer, composer of The Dark Knight Rises , previously wrote and recorded a new composition titled 'Aurora' with all proceeds going to the Aurora Victim Relief organisation.
Watch the music video of Miranda Lambert's 'Over You' below: