This argument is no better than a dogmatic assertion that God is good, even though he appears to be, in human terms, evil. To justify obeying God's commands on a blanket basis, we would still need to prove that all of them were good commands. In Judaism and Islam, God requires the male foreskin to be snipped off. Circumcision in the days before modern medicine was a bloody procedure with risks of infection and even death. But if we pick and choose, then we are simply applying human ethical standards, and God's command is not the basis for our action.
Traditional religions provide no ethical certainties.
Most conventional religions do not offer the certainties that theists look for. It's not at all clear exactly what behaviour God requires of us. His commands are not written in the sky for all to see. Different religions have raised different demands at different times. Islam demands abstention from alcohol, Christian priests dispense alcohol to celebrants of mass.