How can one embrace Islam without joining a group or movement, and is merely uttering the Two Testimonies (Shahadatayn) sufficient, and how can one perform the Hajj pilgrimage without official documents proving one's Islam?

Islam is the relationship between a servant and his Lord, and submission to His commands. Its key is the declaration that there is no god but Allah and that Muhammad is His Messenger. Hajj is not a condition for entering Islam; rather, it is a pillar and an obligation for those who are able, after having embraced Islam, as Allah the Almighty says: (And [due] to Allah from the people is a pilgrimage to the House - for whoever is able to find thereto a way). Obtaining an official certificate of Islam is a means for Hajj, not a condition for entering Islam or performing acts of worship. If a person embraces Islam, he becomes an individual of the Muslim Ummah, bound to Muslims by the bond of Islamic brotherhood, as Allah the Almighty said: (The believers are but brothers).