A common proverb of our day is:  It doesn’t matter what you believe as long as you are sincere.  Sincerity or zealousness is a good thing, but zeal must be guided, directed, submitted.  Paul affirms Israel’s zeal for God but continues, “…they are zealous for God, but their zeal is not based on knowledge.”  May our own attempts to live for God be rooted in knowledge.  That knowledge being that righteousness comes from God.  For we like Israel can attempt to establish our own.