(Imam Bukhari, may Allah have mercy on him, said:) Any Muslim who kept the company of the Prophet ( صلی اللہ علیہ وسلم ) or was blessed to see him is his companion (Sahabi).

Narrated Abu Sa`id Al-Khudri: "Allah's Apostle said, "A time will come upon the people, when a group of people will wage a holy war and it will be said, 'Is there amongst you anyone who has accompanied Allah's Apostle?' They will say, 'Yes.' And so victory will be bestowed on them. Then a time will come upon the people when a group of people will wage a holy war, and it will be said, "Is there amongst you anynone who has accompanied the companions of Allah's Apostle?' They will say, 'Yes.' And so victory will be bestowed on them. Then a time will come upon the people when a group of people will wage a holy war, and it will be said, "Is there amongst you anyone who has been in the company of the companions of the companions of Allah's Apostle ?' They will say, 'Yes.' And victory will be bestowed on them."