Complex sentence: He lived during the sixth century and was a conpemporary of prophet Muhammad was the father of Umar ibn al-Khattab, who would later become Muslim and regarded by Sunni Muslims as the second Caliph, thus he was a Sahaba's ancestor.
Split into simpler sentences: He lived during the sixth century and was a conpemporary of prophet Muhammad. He was also the father of Umar ibn al-Khattab, who would later become Muslim and regarded by Sunni Muslims as the second Caliph, thus he was a Sahaba's ancestor.