From which poem does "heroes from ancient times make teenagers" come from? Who wrote it?

The expression "Heroes have been born as teenagers since ancient times" comes from the folk novel Legend of Sui and Tang Dynasties in Song Dynasty. The original sentence is "Heroes have gone out of purgatory since ancient times", which eulogizes that many heroes in ancient and modern times have made great achievements at a very young age, but they have to go through tempering, fighting, learning and patience. Later, it evolved into "heroes have been teenagers since ancient times." In addition to praise, it is more about trust, exhortation, encouragement and expectation for young people, which is widely spread and known to women and children.

Encouraging young people to study upward can be traced back to the pre-Qin period, when a hundred schools of thought contended and private schools were established to recruit students. Schools take preaching and teaching as their own responsibility, set an example, and constantly encourage and persuade young people to concentrate on their studies and study hard, so as to reserve talents for the country and society. Confucius praised and encouraged young people to be "awesome". Confucius believes that the advantage of young people lies in their physical strength and energy, which is just a good opportunity to learn. When they are young, we should actively learn from them and don't waste their time. Over time, they will have a bright future. Thus, Confucius put forward "there is no class in teaching", and Mencius issued a cry of "educating talents in the world". Future generations all want to be heroes and awesome people when they grow up. In fact, they began to learn and accumulate when they were young. China's understanding and cognition of "learning" in ancient times is broad, which not only refers to the learning at the level of knowledge and technology, but also includes learning, morality, self-cultivation and ambition, thus achieving an indomitable "big self".