In 484 B.C.（the 11th year of Aigong，Duke of the state of Lu），the troops of the state of Qi attacked those of the state of Lu.One of Confucius' disciples，Ran You，being appointed to head the troops of the state of Lu，defeated the enemies in the suburb of Lu.When Ji Kangzi asked him how he learned to fight a battle，Ran You said that he learned from his teacher and he tried to recommend Confucius to Ji Kangzi.Hence，Ji Kangzi sent Gong Hua，Gong Bin and Gong Lin to invite Confucius back to the state of Lu.Now，Confucius ended his 14 years of wandering from one state to another.After Confucius returned to Lu，he was not given any position in the government.However，he had no desire for official posts.Instead he devoted himself to sifting documents and to his teaching.During this period，Confucius made deletion to The Book of Songs and The Book of History，finalized The Book of Rites and The Book of Music，and revised The Book of Spring and Autumn.It was recorded that Confucius had 3，000 disciples，among whom 72 had grasped the "Six Skills".（the Records of the Historian·Confucian Clan）