The Bodhisatta was once a village conch-blower. As a boy he traveled with his father to play at a festival in the city and they made a lot of money. Returning home they had to travel through a forest that was infested with robbers. The Bodhisatta told his father not to blow his conch shell continuously, rather just play it occasionally so the robbers would hear it and assume a large group with an important lord was passing by. But the father felt he knew better and did not listen. When the robbers heard the conch shell blowing continuously, they knew it was not a grand procession, so they went to look. They saw it was just two people walking and they robbed them. Because of the father’s excess, they lost all their money.
In the Lifetime of the Buddha
The father was an earlier birth of an obstinate disciple of the Buddha. The Buddha told him this story of his past life so he knew his refusal to follow advice had previously led to misfortune.