Lifting up the hand against someone represents threatening to harm him. Alternate translation: "if I have threatened to harm fatherless people" (See: [[rc://en/ta/man/translate/figs-metonymy]])
Here "saw" is a metaphor for "knew," "support" is a metaphor for "approval," and "the city gate" is a metonym for the leaders who sit at the city gate. Alternate translation: "I knew that the leaders at the city gate would approve of me" (See: [[rc://en/ta/man/translate/figs-metaphor]] and [[rc://en/ta/man/translate/figs-metonymy]])
This is where the important men of the city would gather to make decisions.
# then bring charges against me
This phrase is not in the original language or in other versions of the Bible. It was added here to help preserve the meaning of Job's statement in this long sentence.