Every push must be a pull
Every push in the Chen Style Taijiquan Practical Method system must be converted into a pull. This is a major concept.
Converting a push into a pull requires a fixed point on the opponent's body. This point must be on the issuer's energy line.
When done properly, this leads to indirect power, which is another Chen Style Taijiquan Practical Method principle.
Source: https://practicalmethod.com/?p=37169