The point of the message was that God is calling us to return to him, but we can't come back to him on our own terms. We must come back his way, and his way involves three commands to return.
RETURN IN REPENTANCE
First of all, we must return in repentance. We can't pretend like nothing has happened. We don't get to ignore the fact that our sin and idolatry has severed our relationship with God. We have to admit that we are wrong, that we have sinned, and we must be truly sorry for it. We can't get back to God unless we first repent of our sin.
RETURN THROUGH GRACE
Secondly, we must return through grace. We come back to God by walking through his grace. We don't make it back to God by our own moral goodness. We can't restore our relationship with him through our own guilt, promises to reform our ways, or our good deeds. A restored relationship with God only happens because of God's grace, manifested by faith in his Son Jesus Christ.
RETURN TO GOD
Finally, we must return to God. The goal of our return is God himself, and a renewed and restored relationship with him. He's not taking us back to some over-idealized version of the past. It's not that we're going back to a time before we had all the baggage we do now, it's that we're finally moving forward with all of our baggage in tow, but now God himself is with us to carry it, redeem it, and use it for good.
This is how we return to God. And he is always ready and excited for us to return. As he says at the end of this passage, "If you will return, then return to me."