You cannot reach deeper within another than you reach in your own self.

If you love yourself for your achievements, your current assets, the way you do things and handle the world — and despise yourself for failure in the same — it follows that your relationship with another will also be transient and superficial.

To achieve deep and lasting love of another person, you need to first experience the depth within yourself — an inner core that doesn’t change with time or events. If it is the true essence, it is an essence shared by the other person as well, and deep love becomes unavoidable.

-Rabbi Tzvi Freeman
“Deep Love”
Based on letters and talks of the Rebbe
Rabbi M. M. Schneerson
Chabad.org

That may explain a few things about what was taught by Jesus and Paul. For instance:

And He said to him, “ ‘you shall love the Lord your God with all your heart, and with all your soul, and with all your mind.’ This is the great and foremost commandment. The second is like it, ‘You shall love your neighbor as yourself.’ On these two commandments depend the whole Law and the Prophets.” –Matthew 22:37-40 (NASB)

Jesus is quoting Leviticus 19:18 when he says that loving your neighbor as yourself is one of the two greatest commandments. Paul says something similar.

Husbands, love your wives, just as Christ also loved the church and gave Himself up for her, so that He might sanctify her, having cleansed her by the washing of water with the word, that He might present to Himself the church in all her glory, having no spot or wrinkle or any such thing; but that she would be holy and blameless. So husbands ought also to love their own wives as their own bodies. He who loves his own wife loves himself; for no one ever hated his own flesh, but nourishes and cherishes it, just as Christ also does the church, because we are members of His body. –Ephesians 5:22-33 (NASB)

Instead of loving yourself, Paul suggests that husbands are to love their wives as they love “their own bodies.” Sounds kind of narcissistic to me. I think most religious people can understand loving God as the ultimate expression of our existence and both religious and secular people can support a husband loving his wife with a great and giving love, but what does this have to do with loving yourself?

As Rabbi Freeman points out, quite a lot, actually.

Strange as it may seem, being a masochistic, co-dependent, doormat kind of giver doesn’t really express love. Love isn’t having to completely devalue yourself in order to show value to another. If love is a mutual transaction between two people, no matter how much you love the other, if you loathe and despise yourself, the other will never be able to love you. How can you love someone who completely treats himself with complete contempt? You might feel compassion or pity for such a damaged person, but a mature and abiding love?

From God’s point of view, the transaction can never be equal since He loves us with a love that no human being can ever achieve. The closest we come to understanding it is the parallel between the Akedah where Abraham so loved God that he was willing to give up his only begotten son for God’s sake (Genesis 22:1-24), and how God sacrificed His most precious Son for us.

For God so loved the world, that He gave His only begotten Son, that whoever believes in Him shall not perish, but have eternal life. –John 3:16

Love doesn’t mean the absence of sacrifice for our own sake but the capacity to sacrifice out of a deep understanding of what love is, including loving the best in ourselves. We were made in His image (Genesis 1:27) and so the best in us is a gift from God.

Therefore you are to be perfect, as your heavenly Father is perfect. –Matthew 5:48 (NASB)

In this, as in so many other things, Jesus became our perfect example of how to be loved and how to love.

“This is My commandment, that you love one another, just as I have loved you. Greater love has no one than this, that one lay down his life for his friends. You are My friends if you do what I command you. No longer do I call you slaves, for the slave does not know what his master is doing; but I have called you friends, for all things that I have heard from My Father I have made known to you. You did not choose Me but I chose you, and appointed you that you would go and bear fruit, and that your fruit would remain, so that whatever you ask of the Father in My name He may give to you. This I command you, that you love one another. –John 15:12-17

Rabbi Freeman talks about loving with an unconditional love and only by loving yourself in that manner do you become capable of loving others and loving God in the same way. That’s quite a task. Very few of us love with absolutely no strings attached. Probably the closest most people come to unconditional love is the love a parent has for a child. An infant isn’t capable of returning love at the same level as a parent, particularly a mother’s love which knows no limits, and if we only love a newborn for the love a newborn can give back, we will be disappointed, and our parental love will be a sham.

But how do we learn to love ourselves and thus others with that amazing “deep and lasting love?” I can’t pretend to give you the answer in absolute terms or say that I have achieved this kind of love with any sort of mastery. I can point to the starting place on such a journey and say that God has showed us that love. In the here and now world, Jesus expressed that love while dying on the cross. If God’s Spirit has any sort of effect in our lives, it is to give us the ability to exceed our human limitations and to exemplify the good inclination within us, shunning the temptation to misuse such a love to serve only our self-contained interests.

1 Corinthians 13 is the so-called “love chapter” and is often recited as part of the vows during wedding ceremonies. However, read within its larger context, Paul is not writing about the love between a man and a woman but love we express toward others that comes from God. Such a love is even greater than faith and perhaps this is because true faith in God emerges from the womb of love. True love of others emerges from God as a flowering plant emerges from fertile soil. It is when we learn to love in this perfect way that our love becomes holy.