Is the money earned by a father from his work in Dar al-Kufr (land of disbelief) lawful or unlawful, knowing that he is the one who provides for his seventeen-year-old son?

It is not permissible to emigrate from Muslim countries to non-Muslim countries for someone who cannot perform the rituals of the religion and fears falling into temptation. However, it is permissible to reside in the land of disbelief for an urgent need or an overriding benefit, provided one's religion and morals are secure. Money earned in the land of disbelief is lawful if its source is lawful, and unlawful if its source is unlawful. Residence itself does not affect the ruling on earnings.