"But the true keys of life are our fellowship with our Lord, and Savior Jesus Christ, for the Bible teaches that no man can enter into the Kingdom of God, except through the son Jesus"

How about Fatherhood of God, Sonship of Man(kind).

i am -> I AM

I AM the Way, the Truth and the Life... maybe Jesus was saying that God who calls Himself I AM is the Way, the Truth and the Life.

Jesus said "what I can do you can do also" - maybe the key to life is to keep these words in mind. Terrifying challenge when you think about it, maybe that is why most don't.

Perseverance is a good Key.

In the beginning we learn or are given the "keys" according to the society in which we start life. Then we start to gather more keys according to our desires & potential. Eventually the keys get in the way because they form the unconscious rule book that replaces the authority that our parents had over us.

So we rebel, awaken, and examine the nature of the keys we have acquired. Eventually we arrive at the one key that unlocks all keys. It is the master key. It's the only key we really need.

That key is "LISTEN TO THE INNER GUIDANCE"

That's what we're here to find out.

And in the end
The love you take
Is equal to the love
You make.

--The Beatles

The key to life is learning to follow our emotions. If we only did things that made us feel good, that would be more than enough to live a fulfiling life.

You have mentioned a couple of emotions in your question which are love and happiness which I think are very much what we should be aiming at experiencing most of the time and spend the least amount of time having negative emotions.

The things that brings us those good feeling emotions are irrelevant as long as they feel good to us. Whether somebody else disapproves is totally their issue. Everyone of us is ultimately only liable for their own connection with eternal conciousness which we achieve by following what feels good to us.

here are the key you are looking for do not judge. jesus refer to stone as judgement in the bible and in the gospel of thomas. http://www.youtube.com/watch?v=2k0RzhVJSxE

Jesus said, "Blessed is he who came into being before he came into being. If you become my disciples and listen to my words, these stones will minister to you. For there are five trees for you in Paradise which remain undisturbed summer and winter and whose leaves do not fall. Whoever becomes acquainted with them will not experience death."

Jesus said, "It is I who am the light which is above them all. It is I who am the all. From me did the all come forth, and unto me did the all extend. Split a piece of wood, and I am there. Lift up the stone, and you will find me there."

Jesus said to his disciples, "Compare me to someone and tell me whom I am like." Simon Peter said to him, "You are like a righteous angel." Matthew said to him, "You are like a wise philosopher." Thomas said to him, "Master, my mouth is wholly incapable of saying whom you are like." Jesus said, "I am not your master. Because you have drunk, you have become intoxicated from the bubbling spring which I have measured out." And he took him and withdrew and told him three things. When Thomas returned to his companions, they asked him, "What did Jesus say to you?" Thomas said to them, "If I tell you one of the things which he told me, you will pick up stones and throw them at me; a fire will come out of the stones and burn you up."

Jesus said, "Show me the stone which the builders have rejected. That one is the cornerstone."

respect your brother and sister free will.

Jesus said, "You see the mote in your brother's eye, but you do not see the beam in your own eye. When you cast the beam out of your own eye, then you will see clearly to cast the mote from your brother's eye."

love them like your self. stay in the truth. the truth will set you free.

http://www.gnosis.org/naghamm/gthlamb.html

I think it is similar to the keys to dreaming. When you really wake up and realize who is creating your experience of life, you are free to choose. Just like when you realize you are creating your dreams, all of a sudden, you can do anything, including controlling the dream itself.

Maybe Jesus was so awake in life that he saw the illusion of reality, and thus could perform the most amazing miracles! To him it was just another choice of how things are in life.

So the keys are "What am I choosing now to experience?" "Is what I am choosing consistent with what I want to experience?"