How do we know Jesus Christ is the true light for Gentiles?

Isaiah prophesied that the coming servant, Jesus Christ, would be a light for the Gentiles and an instrument of salvation unto the ends of the earth. This prophecy is echoed in the New Testament when Paul and Barnabas affirm their mission to preach the gospel to the Gentiles after being rejected by many of the Jews. The fulfillment of Jesus as the light and the accessibility of salvation to all people confirms that He is indeed the true light for Gentiles, as indicated in both the Old and New Testaments.