Are the certificates an employee obtains from training courses in infidel countries unlawful, as is what results from them by way of promotion at work? And is what the employer and employee pay in those countries considered support for their economy, and thus deemed an act of disbelief or a grave sin? And is an employee's travel to those countries for training considered an act of disbelief or a grave sin, knowing that he goes with the intention of benefiting from the certificate for promotion and self-development, and not with the intention of supporting their economy?

Traveling to disbelieving lands is fraught with dangers to one's religion and morals, and is not permissible except under three conditions: knowledge that repels doubts, religiosity that prevents temptations, and the existence of an urgent need. If you are able to openly practice your religious rituals, are safe from temptation, and need the courses, then there is no harm upon you.

Dealing with disbelievers in buying and selling is permissible, as the Prophet, peace and blessings be upon him, dealt with the Jews. As for eating with them and sitting with them in a manner of affection and spiritual loyalty, it is not permissible, and it may constitute disbelief if it involves love for their religion or supporting them against Muslims.