In its modern usage, love is rarely spoken of in relationship to listening. 

In the Bible, love is different. It speaks of husband and wife; of parent and child; and of HaShem and His people. It is there that we learn what real love is - and it always involves listening. If we were speaking Hebrew, that might be enough to make the point - but English makes listening passive. Love is not passive, and it does not simply "go in one ear and out the other." In Hebrew, to sh'ma is to respond. It is not merely hearing – it is reacting to what is spoken. We cannot claim to love G-d, and not respond positively to what He says. To sh'ma is to hear and obey. It is why in Hebrew, the words for "hear" and "obey" is the same: sh'ma.

Followers of Messiah should not wonder if some "obscure commandment" from the "Old Testament" applies to them (there are no "obscure commandments to those who love G-d). 

If you love Me, keep My commandments. 
John 14:15

He who has My commandments and keeps them, it is he who loves Me. And he who loves Me will be loved by My Father, and I will love him and manifest Myself to him. 
John 14:21

If you keep My commandments, you will abide in My love, just as I have kept My Father’s commandments and abide in His love. 
John 15:10

You are My friends if you do whatever I command you. 
John 15:14

Now by this we know that we know Him, if we keep His commandments. He who says, "I know Him," and does not keep His commandments, is a liar, and the truth is not in him.
1John 2:3-4

By this we know that we love the children of G-d, when we love G-d and keep His commandments. For this is the love of G-d, that we keep His commandments. And His commandments are not burdensome.
1John 5:2-3

Do you have ears? Did you hear what the Almighty spoke? Why are you not responding in love, by obeying Him? Sh'ma!