Jesus, the light of the world.

(Jn 8: 12-20) "Again Jesus spoke to them, saying: I am the light of the world; he who follows me will not walk in darkness, but will have the light of life. Then the Pharisees said to him: You you bear witness about yourself; your testimony is not true. Jesus answered and said to them: "Although I bear witness about myself, my testimony is true, because I know where I came from and where I am going; but you do not know where I come from or where I'm going. You judge according to the flesh; I don't judge anyone. And if I judge, my judgment is true; because it's not me alone, but me and the one who sent me, the Father. And in your law is written that the testimony of two men is true. I am the one who testifies of myself, and the Father who sent me testifies of me. They said to him: Where is your Father? Jesus answered: Neither do you know me, neither to my Father; if you knew me, you would also know my Father.

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”These words Jesus spoke in the place of offerings, teaching in the temple; and nobody caught him, because his time had not yet come. "

"Jesus spoke to them again"
Although the feast of tabernacles was over, Jesus had stayed in Jerusalem and was still teaching in the temple. He was not discouraged by the fact that the Jews questioned his person and authority over and over again. And as expected, here we will witness another of Jesus' many controversies with the Pharisees.

"I am the light of the world"
Jesus began by making a statement that included another of the great "I am" of this gospel: "I am the light of the world."

Perhaps the reason why at this time he made such an affirmation we should look for it in what in the previous days had happened in the temple during the feast of tabernacles. There, huge candlesticks had been lit with those who tried to remember the column of fire that led the children of Israel during the nights through their pilgrimage through the desert (Ex 13:21). The relationship with this would not be surprising, since the Lord had already referred to other events of that stage of God's people, such as the manna with which the people had been sustained in the desert (Jn 6: 31-35) or the water of the wounded rock that served to satisfy his thirst (Jn 7: 37-39).

Thus, in the same way that God had enlightened his ancestors in the desert, it was now the same incarnate Son who could enlighten them and disperse the darkness of their hearts. And not only to them, because what Jesus affirmed is that he is the "world" light, indicating with this the universal mission of his ministry. Christ is the light for all men, at all times and places. He is the light in the absolute sense. Any other man or religious movement has no point of comparison with him.
Of course, these words imply that the world needs its light because it is plunged into moral and spiritual darkness. Let us not forget that the world is under the power of the prince of darkness and that only the Lord Jesus Christ can change this situation.

Now, if any man spoke in this way, everyone would immediately think that he is crazy, but the absolute moral purity of Jesus and the profound wisdom with which he spoke, have led many people to believe that what he said was the truth and that He really is the Light of the world.

John had already announced this at the beginning of his gospel: "That true light, which enlightens every man, was coming to this world" (Jn 1: 9). And with his coming began to fulfill what the prophet had announced:
(Mal 4: 2) "But to you who fear my name, the Sun of Justice will be born, and in its wings will bring salvation ..."

"He who follows me will not walk in darkness"

The Jews could question the claim Jesus had just made, but it was very easy to see if what he had said was true or not. To do this they would only have to observe those who followed him and see if they were in darkness.

Credits for luis de miguel from the biblical school.