His paintings speak louder than words.

Meaning: This means the artist's paintings are so powerful and expressive that they can convey more meaning than words can.

Choice of Words: Paintings are pictures or designs made with paint. Speak means to make sounds with your mouth in order to communicate. Louder means making more noise. Words are spoken or written symbols that represent ideas or objects. When you put them together, it means his paintings communicate more effectively than words.