Sahih Al Bukhari (634)

عن أنس (رضي الله عنه) قال "مر على النبي (صلى الله عليه وسلم) بجنازة فأثنوا عليها خيرا فقال وجبت ثم مر بأخرى فأثنوا عليها شرا أو قال غير ذلك فقال وجبت فقيل يا رسول الله قلت لهذا وجبت ولهذا وجبت قال شهادة القوم المؤمنون شهداء الله في الأرض"

Anas narrated: A funeral procession passed in front of the Prophet (peace be upon him) and the people praised the deceased. The Prophet (peace be upon him) said: "It has been affirmed (Paradise)." Then another funeral procession passed by and the people talked badly of the deceased. The Prophet (peace be upon him) said: "It has been affirmed (Hell)." Allah's Messenger (peace be upon him) was asked: "O Allah's Messenger! You said it has been affirmed for both?" The Prophet (peace be upon him) said: "The testimony of the people (is accepted), (for) the believer are Allah's witnesses on the earth."