Islam, an Arabic word which, since Prophet Muhammad's time , has acquired a religious and technical significance denoting the religion of Muhammad and of the Qur'an, just as Christianity denotes that of Jesus and of the Gospels, or Judaism that of Moses, the Prophets, and of the Old Testament.
Grammatically, the word Islam is the infinitive of the so-called fourth verbal form of the regular intransitive stem salima, "to be safe", "to be secure", etc. In its second verbal form (sallama) it means "to make some one safe" and "to free", "to make secure", etc. In its third form (salama), it signifies "to make peace", or "to become at peace", i.e. to be reconciled". In its fourth form (aslama), the infinitive of which is Islam, it acquires the sense of "to resign", "to submit oneself" or "to surrender". Hence Islam, in its ethico-religious significance, means the "entire surrender of the will to God", and its professors are called Muslimun (sing. Muslim), which is the participial form, that is "those who have surrendered themselves", or "believers", as opposed to the "rejectors" of the Divine message, who are called Kafirs, Mushriks (that is those who associate various gods with The Deity), or pagans.