Proselytism /ˈprɒsəlᵻˌtɪzəm/ is the act of attempting to convert people to another religion or opinion. The word proselytize is derived from the Greek language prefix προσ- (pros-, toward) and the verb ἔρχομαι (érchomai, to come) in the form of προσήλυτος (prosélytos, a new comer). Historically in the Koine Greek Septuagint and New Testament, the word proselyte denoted a gentile who was considering conversion to Judaism. Though the word proselytism originally referred to Early Christianity (and earlier Gentiles such as God-fearers), it now refers to the attempt of any religion or religious individuals to convert people to their beliefs, or any attempt to convert people to a different point of view, religious or not. Proselytism is illegal in some countries.
In the writings of the Bahá'í Faith, the endeavour to attract people to the religion is strongly emphasized. The process of attracting people to the religion is referred to as teaching. The term proselytism is given the connotation of aggressively teaching the religion to others, and is prohibited.
Every Bahá'í has the obligation of teaching their religion, as it is seen as the path toward bringing peace and justice to the world. Some Bahá'ís move to other countries or cities where there are a small number of Bahá'ís to help spread the religion, and this is called pioneering. Some other Bahá'ís move from place to place in a process called travel teaching. When moving or travelling to other countries Bahá'ís are encouraged to integrate into their new society and apply Bahá'ís principles in living and working with their neighbours. In total, however, only a small minority of Bahá'ís are directly teaching their religion to others. Despite this, religion has grown "at least twice as fast as the population of almost every UN region" over the last century.