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https://www.biblegateway.com/passage/?search=John+8%3A12-30&version=AMP

Bible Hub Commentary John 8:12
https://biblehub.com/commentaries/john/8-12.htm
Ellicott's Commentary for English Readers
He that followeth me (Jesus) shall not walk in darkness.—Strong and full of hope as these words are in the English rendering, the Greek is more emphatic still. The negative is in its strongest form, expressing “shall by no means,” “shall in no wise,” “walk in darkness.” The possibility is excluded from the thought. “God is light, and in Him is no darkness at all.” If a man makes a false step in life, it is because he seeks other guides in his own thoughts or in subjection to the thoughts of other men. He that seeks to follow the true Light—to follow, not precede it; to follow always, not only when it coincides with his own will; to follow patiently and trustfully, step by step, wherever it may lead—cannot walk in darkness, for he is never without the presence of the Light. Here, as so often, stress is laid on the certainty and universality of the divine love on the one side, and the action of the human will on the other. There can be no doubt, “shall by no means walk in darkness”; there can be no limit, “he that followeth”; there can be no halting, “he that followeth.” The light ever points the way; it is he who day by day follows it who cannot miss the way. Perception of truth attends its practice. The true journey of this life is here presented as a constant activity; in John 7:37, the source of this action is found in a constant receptivity.