The mitzva of charity is not the only one described as being equal to all the other mitzvot.
This declaration is also made with regard to each of the following mitzvot (among others): tzitzit ; circumcision ; and Torah study.
In a certain sense, all the mitzvot form a single, unified structure in which each mitzva is viewed independently of the others.
Each one possesses a unique function not shared by the other mitzvot.
Having said this, there are certain mitzvot that are more universal in nature, relating to, and interconnected with, the other mitzvot comprising this grand structure.
One such mitzva is that of charity.
Rabbi Adin Steainsaltz