法輪 is the Chinese, Japanese Kanji, and old Korean Hanja title, “The Eternal Wheel of Life,” in Buddhism.

Also known as the wheel of the law, or Buddha-truth, which can crush all evil and all opposition. It is likened to Indra's wheel, which rolls on from man-to-man, place-to-place, age-to-age.

Colloquially used in some sects to mean preaching or spreading Buddha-truth.

There are several ways to translate this ancient proverb. Translated literally and directly, it says, “Open roll has/yields benefit.”

To understand that, you must know a few things...

First, Chinese characters and language have deeper meanings that often are not spoken but are understood - especially with ancient texts like this. Example: It's understood that the “benefit” referred to in this proverb is to the reader's mind. Just the last character expresses that whole idea.

Second, Chinese proverbs are supposed to make you think and leave a bit of mystery to figure out.

Third, for this proverb, it should be noted that roll = book. When this proverb came about (about two thousand years ago), books were rolls of bamboo slips strung together. The first bound books like the ones we use today did not come about until about a thousand years after this proverb when they invented paper in China.

開卷有益 is a great gift for a bookworm who loves to read and increase their knowledge. Or for any friend that is or wants to be well-read.

Some other translations of this phrase:
Opening a book is profitable
The benefits of education.