Is working in a non-Islamic bank to market credit cards permissible or forbidden?

As long as the bank is not Islamic, it is impermissible to work in it, especially in marketing its products, due to the promotion and assistance this entails. The Prophet, peace and blessings be upon him, cursed the one who consumes usury, the one who feeds it, its scribe, and its two witnesses, and they are all equal in sin. This indicates the prohibition of assisting in falsehood. A Muslim must fear Allah and seek permissible work, for the ways of lawful earning are many, and sustenance is apportioned, and no soul will die until it has received its full share. Therefore, one must seek sustenance through obedience to Allah, not through disobedience to Him.