This quote expresses two interconnected ideas about human nature and morality. The first part, "Good-nature and good-sense must ever join," suggests that kindness and wisdom are inseparable qualities that should always coexist. One can’t truly be kind without being wise, and one can’t truly be wise without being kind. It implies that a person who is good-natured but lacks good sense might be naive or easily manipulated, while a person with good sense but lacking good-nature might be cynical or indifferent to others’ suffering. So, for a person to be truly virtuous, they must have both a kind heart and a wise mind.

The second part of the quote, "To err is human, to forgive, divine," speaks to the inevitability of human error and the moral superiority of forgiveness. It acknowledges that making mistakes is a part of being human. However, the ability to forgive those mistakes is associated with divinity, suggesting that forgiveness is a virtue that elevates us above our human flaws.

In today’s world, this quote can be applied in numerous ways. In the context of personal development, it encourages us to strive for both wisdom and kindness in our interactions with others. It also reminds us to be forgiving, both towards ourselves and others, as everyone makes mistakes. This can lead to personal growth, healthier relationships, and a more compassionate society.

In a broader societal context, these ideas can be applied to issues like criminal justice reform, where an emphasis on punishment could be replaced with an emphasis on forgiveness and rehabilitation. Similarly, in politics, leaders who embody both good-nature and good-sense are likely to make decisions that consider the welfare of all, rather than serving their interests.

In conclusion, this quote encourages us to strive for a balance of kindness and wisdom, and to practice forgiveness, elevating our human nature towards the divine.