I don't know if I'm too late to contribute to this line of discussion, but it strongly reminds me of trying to understand the Hebrew word hhesed, which is variously translated as lovingkindness, kindness, love, mercy.
I read a Rabbi who said that the true meaning of the word on God's part was loyalty to the Covenant. Not "God will show his love" or "God will be merciful" but rather "God will be faithful to the Covenant, will uphold His end of the deal."
And God's end of the deal is that He will be our God. "Hear O Israel, the Lord our God, the Lord is One" (or the Lord is our God, the Lord alone).
This is the reply that Jesus gives in Mark when asked what the greatest commandment is. Before telling us to love God & neighbour, Jesus recites this statement of faith reminding us of the Covenant with Abraham. In essence, the greatest commandment is the Covenant.
The terms of the Covenant with God are the Torah, the Law. And the 2 commandments of Love that Jesus teaches sum up the Law.
When Jesus commands us to Love, could we not substitute Be Faithful to the Covenant (and the obedience to the Law that that implies)?
The point that the Greatest Commandment begins with the Shema Yisrael is worth exploring, I think, even for us presumptive monotheists. And how far does faithfulness to His Covenant get us to God's lovingkindness, or even to "God is Love"?