44 And Jesus cried out and said, "He who believes in Me does not believe in Me, but in Him who sent Me.
45 "And he who beholds Me beholds the One who sent Me.
46 "I have come as light into the world, that everyone who believes in Me may not remain in darkness.
Jesus' words here are remarkably similar to what He said when He commissioned His disciples in Matthew 10:40: "Whoever receives you receives me, and whoever receives me receives him who sent me." And look at what He is about to say in the next chapter, John 13:20: "Truly, truly, I say to you, whoever receives the one I send receives me, and whoever receives me receives the one who sent me."
This concept of sending and receiving seems to be important, at least for those of us who want to take advantage of Jesus as being the True and Living Way to the Father. If you would receive God, you must receive Jesus His Son, whom He sent. If you reject Jesus whom He sent, there is no other way to God.
The word "apostle" comes from two Greek words meaning "sent out." The apostles were "apostles of Jesus Christ" (see I Peter 1:1, Colossians 1:1, and the first verses of most of the epistles for examples), i.e., they were "sent out by Jesus Christ." You also see some people in the New Testament being billed as "apostles" of certain churches; what we might refer to as "missionaries." But Jesus Himself is an Apostle. Indeed, He is the Apostle, the one sent out by God for the most important "mission" in history: the rescue of lost humanity and the redemption of creation. He describes this mission in verse 46: "I have come as light into the world, so that everyone who believes in Me may not remain in darkness."
Jesus mandated that in order to receive Him (which is necessary for receiving God), we must receive His apostles in their apostolic mission, and likewise we must accept His sayings, His words, His commandments, His teaching. In fact, these are one and the same, since Jesus sent the Holy Spirit to guarantee the apostles' mission of teaching His Gospel.
47 "And if anyone hears My sayings, and does not keep them, I do not
judge him; for I did not come to judge the world, but to save the world.
48 "He who rejects Me, and does not receive My sayings, has one who
judges him; the word I spoke is what will judge him at the last day.
49 "For I did not speak on My own initiative, but the Father Himself
who sent Me has given Me commandment, what to say, and what to speak.
50 "And I know that His commandment is eternal life; therefore the things I speak, I speak just as the Father has told Me."
It is mandatory (and, frankly, extremely blissful) to accept Jesus' teachings (including the teachings expressed through His apostles!) as the word of God. As the apostle Paul put it "we also constantly thank God that when you received from us
the word of God's message, you accepted it not as the word of men, but
for what it really is, the word of God, which also performs its work in
you who believe." 'Tis so sweet to trust in Jesus!