This verse is part of the Parable of the Prodigal Son, a story Jesus tells to illustrate God's boundless forgiveness. Here's a breakdown of the verse's meaning within that context:

"When he had spent all of it...": This refers to the younger son who, having demanded his share of the inheritance from his father, went to a distant country and recklessly squandered all his wealth on extravagant and irresponsible living. It highlights the consequences of his choices.

"...there arose a severe famine in that country...": This adds to the son's misfortune. Beyond his own foolish spending, external circumstances (the famine) exacerbate his situation. It signifies that sometimes, hardship can come not just from our own actions but also from unpredictable events.

"...and he began to be in need.": This is the pivotal moment where the son's carefree existence crashes. He experiences genuine hardship, lacking even basic necessities like food and shelter. It underscores the stark reality of the consequences of his actions and marks the beginning of his journey toward humility and repentance. It shows the contrast between his previous abundance and his current desperate state.

In a broader sense, the verse means:

Consequences of wastefulness: It illustrates the principle that irresponsible actions often lead to negative outcomes.
The fleeting nature of worldly possessions: It emphasizes that material wealth is not a source of lasting happiness or security.
The importance of humility: The son's neediness forces him to confront his pride and consider the error of his ways.
The opportunity for repentance: The verse sets the stage for the son's realization that he needs to return to his father.

In essence, this verse is a key turning point in the parable. It depicts the prodigal son's fall from grace, brought about by his own foolishness compounded by external circumstances, forcing him to confront the reality of his situation and setting him on the path toward repentance and reconciliation.