Together, they create the vivid image: “Sources of wealth (财源) are rolling and rolling (滚滚)” toward you.
In Chinese culture, wishing prosperity and good fortune upon others is a common and important social custom. It is not considered greedy but rather a practical and heartfelt desire for security, success, and the ability to provide for one's family. “财源滚滚” is a cornerstone of this tradition. A useful Western comparison is the phrase “to be rolling in the dough.” However, there's a key difference. “Rolling in the dough” usually describes a person who *is already* wealthy and enjoying their riches. 财源滚滚 (cáiyuán gǔngǔn), on the other hand, is almost always used as a forward-looking wish or blessing *for someone else*. It focuses on the process of wealth arriving—a continuous, dynamic flow—rather than the static state of being rich. It reflects the cultural value of wishing for ongoing success and sustainable prosperity, not just a one-time windfall.
This phrase is extremely common and is used in a variety of positive, celebratory contexts.