Ibn Majah narrated that it was asked, “Who are the strangers?” The Prophet Muhammad (pbuh) responded, “Those (few) who left their tribes (for Islam)” (Ibn Majah).
In another version, the Prophet Muhammad (pbuh) responded to the question by stating, “Those that correct the people when they become corrupt” (Abu Amr al-Dani, Al-Albani graded it authentic in Sahihah (3/267)).
In another narration he said in response to the same question, “They are a small group of people among a large evil population. Those who oppose them are more than those who follow them” (Ahmad, Al-Albani graded it authentic in Sahihah (4/153)).
The Prophet Muhammad’s (pbuh) statement “Islam began as something strange“ means that before his coming the people were on misguidance. So Allah sent him to guide the people to the truth. It is reported that the Prophet (pbuh) said, “Verily, Allah looked at the people of Earth with disdain, the Arabs and the non-Arabs, except for some of the remnants of the People of the Book (i.e., the Jews and the Christians)” (Muslim).
When the Prophet Muhammad (pbuh) was sent and began to call the people to Islam, there were only a handful of people from various tribes that responded to his call. Those that responded were fearful of their families and tribes that they may severely harm or hurt them.
However, they remained patient for the sake of Allah. The Muslims at that time were weak. They were expelled and displaced from their homes and were made to flee to remote countries. They were twice forced to migrate to Abyssinia and then finally to Medina. Among them were those who were punished and tortured for the sake of Allah and those who were killed. During that time those entering into Islam were considered ‘strangers’.
Then Islam became established in Medina and became strong. It’s people became visible in all aspects. Afterwards, the people began to enter Islam in large crowds. Allah made the religion clear to them and completed His favor upon them. Then the Prophet Muhammad (pbuh) died yet the Muslims stayed firm on their religion. They collaborated and supported one another during the time of Abu Bakr and Umar.