—such as medical treatment, trade, or specialized education in beneficial disciplines that cannot be obtained except by travelling to them. Such travel is permitted only to the extent of the need; once the need has ended, one must return to Muslim lands.

The permissibility of this journey is also conditioned upon the traveler’s openly upholding his religion, taking pride in his Islam, steering clear of places of corruption, and remaining alert to the schemes and intrigues of the enemy. Likewise, travelling to their lands is permissible—and may even become obligatory—when the purpose is to invite people to Allah and spread Islam.

4. Assisting them, supporting them against Muslims, praising them, or defending them.
   This is among the nullifiers of Islam and the causes of apostasy—we seek Allah’s protection from it.

5. Seeking their help, placing confidence in them, and appointing them to posts that involve the confidential affairs of the Muslims.