Psalms (4 weeks): see R. Jacobson’s 6-week series (2015)
6/16 Psalm 113 (Luke 15:8-10)
6/23 Psalm 69:1-16 (Matthew 7:7-11)
6/30 Psalm 27:1-6 (Matthew 6:25-34)
7/7 Psalm 40:1-10 (Luke 17:11-19)
As a singular noun, "sin" points to the world's collective alienation from God. "Sins" in the plural evokes a catalog of individual misdeeds and "sinful" behaviors, which is not what John is saying here. "Sin" in the singular refers to a broken relationship with God in which we all share equally, whereas "sins" in the plural can be used to point to some relationships and behaviors as more broken than others. As the Passover Lamb, Jesus liberates the world from slavery to "sin" by bringing the world into new and fresh contact with the presence of God, so that human alienation from God can end.
Eight of the ten words begin: "you shall not." People often speak of negative commandments as off-putting "do nots" that constrict life....But that misconstrues the negative instructions in the Torah. First, we can keep all of them while taking a nap. ...Second, negative mitzvoth deal with the parameters of behavior. They do not specify what we should do, simply what we should not do. They name the actions that cancel all possibility of living with others a life of well-being (which can only be lived with others.)