John Lewis’s stand on the war against Iraq in 1991 was not surprising for two reasons.  First, Lewis was never afraid of taking positions that were not popular.  Second, he was opposed to the Vietnam War on moral grounds.  The article that your question is taken from says that he was a conscientious objector who was opposed to all war.

As someone who was a leader in the Civil Rights Movement, John Lewis was used to taking stands that were unpopular.  As your article says, he was beaten many times by people who opposed civil rights.  Even so, Lewis kept pushing for what he believed was right.  This shows quite clearly that he would not be likely to back down from a position just because it was unpopular.

More importantly, Lewis felt that violence was simply wrong.  We can see this from his statement (in your last question) about how violence debases people.  Because Lewis hated violence, he was a conscientious objector to the Vietnam War.  He felt that all wars were wrong because all wars are violent.  If Lewis believe that all wars were wrong, it would stand to reason that he would oppose the Gulf War in 1991.

From this, we can see that Lewis’s stand in 1991 was not surprising.  He clearly disapproved of all violence and he proved many times that he was willing to take unpopular positions even if doing so could harm him.  Therefore, we should not be surprised that he was opposed to the war against Iraq.