The name Arpakshad (אַרְפַּכְשַׁד) identifies a son of Shem, born two years after the flood (Genesis 11:10). He is listed in both the Shem genealogy (Genesis 10:22–24; 11:10–13) and Luke 3:36 in the Messianic lineage running through Noah to Abraham to Jesus. Arpakshad lived 438 years and fathered Shelah.
Arpakshad's significance lies entirely in his position in the covenant genealogy. From Shem's line specifically, God preserved the seed of blessing that would lead to Abraham, Isaac, Jacob, and ultimately to Christ. Arpakshad represents the critical link between Shem and Shelah, and through Shelah to Eber (from whom Hebrew may derive its name), and ultimately to Abraham. Luke 3:23–38 presents Jesus' genealogy through this exact line, affirming that the Messiah was truly 'the son of Adam, the son of God.'