Q2, (1:2) Why do forgiveness (sprinkling) and obedience come together as a package? Why is it deceptive to think you can have one without the other?
You must be obedient to Jesus Christ in order to receive His forgiveness for you can't have one without the other. Many of us who seek forgiveness for our sins, but refuse to listen or follow him, don't have true faith. "Faith by itself, if it is not accompained by action is dead" (James 2:17)
Extra Credit: If true faith requires obedience, how can we say that we are saved by grace rather than works?
Because it is a gift of God. It is through God's grace that we are saved, not by any ability, effort, choice, or act of service on our part. It is because of this gift that we show our gratefullness through acts of love and kindness and service to Jesus Christ.