certainty because it is mentioned by several of them, is highly uncritical."
Life of Mohammad, p. 73.

The sources whence Muhammad derived the materials of his Koran are, over and
above the more poetical parts, which are his own creation, the legends of his
time and country, Jewish traditions based upon the Talmud, or perverted to
suit his own purposes, and the floating Christian traditions of Arabia and of
S. Syria. At a later period of his career no one would venture to doubt the
divine origin of the entire book. But at its commencement the case was
different. The people of Mecca spoke openly and tauntingly of it as the work
of a poet, as a collection of antiquated or fabulous legends, or as palpable
sorcery.4 They accused him of having confederates, and even specified
foreigners who had been his coadjutors. Such were Salman the Persian, to whom
he may have owed the descriptions of Heaven and Hell, which are analogous to
those of the Zendavesta; and the Christian monk Sergius, or as the
Muhammadans term him, Boheira. From the latter, and perhaps from other
Christians, especially slaves naturalised at Mecca, Muhammad obtained access
to the teaching of the Apocryphal Gospels, and to many popular traditions of
which those Gospels are the concrete expression. His wife Chadijah, as well
as her cousin Waraka, a reputed convert to Christianity, and Muhammad's
intimate friend, are said to have been well acquainted with the doctrines and
sacred books both of Jews and Christians. And not only were several Arab
tribes in the neighbourhood of Mecca converts to the Christian faith, but on
two occasions Muhammad had travelled with his uncle, Abu Talib, as far as
Bostra, where he must have had opportunities of learning the general outlines
of Oriental Christian doctrine, and perhaps of witnessing the ceremonial of
their worship. And it appears tolerably certain that previous to and at the
period of his entering into public life, there was a large number of
enquirers at Mecca, who like Zaid, Omayah of Taief, Waraka, etc., were
dissatisfied equally with the religion of their fathers, the Judaism and the