Only its missionary spirit is different from that associated with the proselytizing creeds. It did not regard it as its mission to convert humanity to any one opinion. For what counts is conduct and not belief. Worshipers of different Gods and followers of different rites were taken into the Hindu fold. The ancient practice of vratyastoma, described fully in the Tandya Brahmana, shows that not only individuals but whole tribes were absorbed into Hinduism.
Many modern sects accept outsiders.
Dvala's Smriti lays down rules for the simple purification of people forcibly converted to other faiths, or of womenfolk defiled and confined for years, and even of people who, for worldly advantage, embrace other faiths. Ardha-Hindus include not only Westerners who have taken a Hindu first name, but Easterners who have taken a Western name, first or last, to disguise their true Hindu name or to render it easier for Westerners to pronounce. Other religions abhor this. For instance, in the Islamic community we would never meet Mohammed Ali Johnson or Joe Mohammed. They are proud to be who they are, abhoring all disguises.