The next weakness will probably be on the compassion: every effort we take being for the benefit of all others. If that is weak, we are going to deprive ourselves of the root of the Mahayana practice. Mahayana doesn’t care for selfish interest, it cares for all sentient beings. The basic principle of Theravada is self-interest. That is why an individual needs to practice the Theravadin basic principle of self-serving and in addition to that the Mahayana basic principle of serving others. Serving others, caring for others does not mean ignoring yourself. It becomes most important to care for yourself too, because if you are not there who is going to serve? That is an important point.
To make a strong commitment for helping other sentient beings, a very basic Mahayana foundation is the strong love-compassion to all sentient beings. So it becomes necessary to practice the mind of the bodhisattva, the bodhimind, trying to develop it through the prayer form and through following carefully the vows of the bodhisattva.
~ Gelek Rimpoche, The Six Perfections, 2013, p. 12