I've known too many sincere Christians that have been less than convinced that God really loved them. They thought, well he tolerates me, or he is always frustrated with me, and they've never been able to rest in the Father’s abiding, deep love for them.
Yet redemption starts with God’s nature, his absolute and unquenchable love for his people. God made us for this very reason—so that in Christ we can be his beloved children.
The study we are going through in Sunday School has been helpful and thanks to Google documents I can at least share the slides with you.
Sources cited (besides Peterson's book): Heirs with Christ (Beeke), Communion with the Triune God (Owen), Communion with God (Kapic)