大乘起信論義記 3.415

3.415

"How is the gate of vigor practiced? It refers to having a mind that is neither indolent nor retrogressing in all wholesome matters, establishing a resolute determination and staying far away from cowardice. One should be mindful that from the distant past onward, one has vainly suffered all kinds of great physical and mental pain without any benefit; therefore, one should diligently cultivate all virtues, benefiting oneself and others, and swiftly leaving all suffering behind."