Job 9:3

If he will contend with him, he cannot answer him one of a thousand.

The verse belongs to the debate between Job and his three friends about his afflictions in chapters 4 to 31, spoken as part of three circles of speeches by each, within what has come down as the oldest poetical book, thought by many to be the oldest book in the Bible and conjectured, though not known, to have been written by Moses in the land of Midian. Within that debate it is part of Job's response and arguments with his friends about the cause and purpose of human suffering, affirming that affliction does not prove sin. If a person will contend or dispute with God, or God brings a case against him and calls him to account, he cannot fully or successfully answer Him, not even one in a thousand, whether framed as answers, questions, or charges. This inability emphasizes human weakness before God's overwhelming wisdom and power.

Brought into judgment, a person cannot justify himself before God by his works, for he cannot answer even one charge out of a thousand, so human works cannot provide the ground for justification. The verse belongs to the description in Job 9:2-8 of God's unanswerable power, including treading on the waves of the sea, which is seen when Jesus overtook the disciples by walking on the sea. It illustrates how Israel's wilderness trials exposed their inability to answer God's tests: like pupils unable to answer even one question in a thousand, they were humbled, so that to be unable to answer was to be humbled.