Let's suppose that, before time began, there was just God. And let's suppose that when the Bible says that "God is love" that such a claim is true - God and love are synonymous.
OK, now let's imagine that God wanted to expand love. I am not exactly sure how God gets bigger or love expands when there is only God. If God is infinite, then how do you get more infinity? But let's suppose that God figured that there is a way to increase love despite the fact that God and love are already infinite.
Perhaps God needed to create a new category of reality which has a capacity for love and it could be filled with love. Perhaps God created a sort of "not-God" whch could become more like God, were it willing to do so.
So, let's suppose there wasn't anything but God when God starting plotting on the expansion and increase of love. So, in order to fulfill the dream of making more love God creates a universe. Let's also assume God could have done it in six days or God could have initiated a 6 billion year process, but that the "how" is irrelevant.
So, now there is God and "not God." The "not-God" kind of resembles the God, but it is clear that two are distinct. We must remember that love is being expanded, not just made more known for what it is already.
God creates humans in the midst of this incredible creation of plants and animals and waters and lands and skies. Within the humans, at least, and perhpas within everything comprising creation, there is an infinite capacity for love. So, rather than a single infinite location for love to exist, there are billions of potential infinite love locations.
Now, God decides to place these individuals in relationship with each other through biological, emotional, and spiritual networks called families. New people are added to the creation not from the dust of the eargth, but rather from the people themselves. Families are formed. Generations are formed. Now there is not merely infinity contained within a person, but infinity shared between two or even multiple people.
So, if this is all true, God has entrusted a capacity for love and by definition a capacity for Himself, to individuals and therefore through relationships, God has entrusted the perpetuation and expansion of love adn even Himself to families.
Step back and think about that for a moment. Why would God do such a thing? Was God naive and think that people would make only good decisions? Did God believe people would actually use that capacity to love and actually fill it with love? Was God wise in releasing such capacity for depth within and between people knoing that there was no promise by the recipients that they would even bother to try?
The risk to release love to the structure of family was huge.
But the risk was not lost on God. The bible clearly says that God knew of the risk. "The sins of the fathers will visit the third and fourth generation." This was no mystery to God. And oh how true it is that these sins pay multiple visits. Children who are abused, children of alcoholics, children of hate-filled marriages, children of liars (the list could go on for quite some time) - they all experiene something ranging from unpleasant to completely debilitating when their parents fail to fill their infinite capacity for love with love.
However, God saw that the results were better when love did fill that eternal capacity. God's faithfulness lasts for a 1,000 generations. Here is what makes it worth the risk. A little bit of love goes a long way. It goes a long way because we were made for it. Love is powerful because when it connects with the eternal capacity within each of us and especially between us within our families, it is making God's dream of the expansion of love come true.
Love entering into new ground is God's dream coming true.
This is why the two greatest commandments have to do with loving God and loving people. It is God's dream come true. The law and prophets hinge on these and rendered utterly useless without them.
God has placed people within families because that is the best and most likely context in which love can be learned. From there, it can spread to friends, to neighbors - to enemies.
Of course it is no guarantee. God is a fan of free will. And yet, God is convinved that people, when given the free will chance to choose love, will choose it. God is banking on families to be nesting grounds of the expansion of love and therefore the expansion of God Himself.