Master Golden Sword said that this sword technique was only taught to third senior brother Li Yuan Qing. Even Zhou Yun Feng was not taught it, because cultivation of it is extremely difficult.
After understanding his high enlightenment towards swordsmanship through the previous Wind Thunder Sword Technique, he decided to pass it on.
Lin Yi naturally understood that Master Golden Sword did not pass this sword technique to him because of his enlightenment. Instead, he was worried that Lin Yi, who was about to accomplish Perfect Foundation Building and had a minimal chance of forming his Golden Core, would face some mishaps from idleness in the next hundred years. Therefore, he passed this sword technique to him so that he could research it further in his spare time.