God is Love

A couple weeks ago in Sunday School, one of the questions (I think from the manual) was Why is it appropriate to say that God is love? We had difficulty answering that question, largely I think because we didn't quite understand what was being asked. It later occurred to me that asking instead what does "God is love" mean? probably would lead to the sort of answers the manual writers were looking for. And I think that basically means that love is the defining characteristic of His character.

But during the lesson, as the discussion about that first question was going on, I thought of one of the questions asked of Christ during His mortal ministry.

But when the Pharisees had heard that he had put the Sadducees to silence, they were gathered together. Then one of them, which was a lawyer, asked him a question, tempting (or testing) him, saying, Master, which is the great commandment in the law?
Jesus said unto him, Thou shalt love the Lord thy God with all thy heart, and with all thy soul, and with all thy mind. This is the first and great commandment. And the second is like unto it, Thou shalt love thy neighbour as thyself. (Matthew 22:34-39)

And since we are told to be perfect, even as our Father in Heaven is perfect, doesn't it just make sense that the greatest commandment is to gain the characteristic that John uses to define Him?