Read the following text and answer the question.

An old man on the point of death summoned his sons around him to give them some parting advice. He ordered his servants to bring in a bundle of sticks and said to his eldest son, “Break it.” The son strained and strained, but with all his efforts, he was unable to break the bundle. The other sons also tried, but none of them was successful. “Untie the bundle,” said the father, “and each of you takes a stick.” When they had done so, he called out to them, “Now, break,” and each stick was easily broken. “You see my meaning,” said their father.

Source: High Interest Reading Comprehension Skills & Strategies Level 5

What was the father’s meaning in doing that?