# dispute

in this case a legal complaint, argument, or disagreement

# does he dare ... holy people?

"it is wrong for him to dare ... holy people." or "he should fear God and not ... God's holy people." 

# to bring a lawsuit before the unrighteous rather than before God's holy people

Paul teaches that a Christian should not take another Christian to court before a non-Christian judge. Christians will judge the angels, so they should be able to solve problems among themselves. It is better to be cheated.