Complex sentence: The Testament of Adam is a Christian pseudepigraphical work extant in Syriac and Arabic, believed to be 6th CE as we have it but 4th century CE in origin, probably composed in Edessa.
Split into simpler sentences: The Testament of Adam is a Christian pseudepigraphical work extant in Syriac and Arabic. The earliest manuscript is dated to the 6th century, but the text is 4th century CE in origin, probably composed in Edessa.