Joy and sorrow is only an idea or thought!
Thoughts are not Real and they are passing clouds!
We use certain terms without knowing the real meaning. It is a mere feeling and the feeling is only a thought. What you consider joy or sorrow is but a pattern of thought. One says, "I am happy" and the other one laments, "I am sad". Both are merely expressing their thoughts and what are thoughts but passing clouds. They have no reality. The feeling of joy or sorrow is a temporary feeling or thought. None remains ever in joy or in continuous sorrow. Even if some one laughs, it is only for few moments. Crying may take a little more time since the sad thought weigh in the mind. Feelings of elation pass off quickly. If you look at this deeply, every thing is but mind's play!
Here, i would like to go deep into the term 'mind' and thought. There is no such thing as mind except they are bundle of thoughts. What is a hanky except a criss cross of thread woven in such pattern? A piece of cloth is nothing but threads that go in both directions and closely knit. Remove the thread one by one. There is no such thing as the piece of cloth! Likewise, the mind seems to be a place where thoughts hover around always. Distracting thoughts, sad thoughts and very rarely pleasant thoughts. Yes, the pleasant thoughts are rare since man has habituated into negative thinking only. We all worry about the past mistakes and feel guilty. We always worry about the future prospects. In both the cases, the mind is agitated and peace is lost. If you examine a little more, the mind will never dwell on the "Present moment"
Let us again examine the term "Present moment". It is nothing but "Omnipresent". A great Truth is there was no such thing as 'past or future". Every thing happened only in the present moment. With respect to the present only, we use wrong terms like past and future. Past is a memory. Future is fear. Hold on to the Present moment and remain at Peace. If the mind is turned to focus only on the Present moment, the mind will vanish! Mind exists because of the past and future. You can make the fly sit on anything except fire. The fly won't go near the fire. Likewise, the present moment is anathema to the mind. I said, that the present moment is Omnipresent. How? All along, there is only present moment. The past and future are the figment of imagination of the mind. When I assert "I exist", I am talking about the present moment only. The fact is "I am always existing". This is the eternal truth of all philosophies.
This is the voice of God, "I am". God exists. That is all. There is no past or future. He is always present and hence he is termed as Omnipresent. Nothing else exists apart from the "I" or God. Hence, the mind is a great illusion which came out from the "I" during creation. One more fact is "God alone exists! Then what about our perceptions of diversity? The Advaitins who practice "monism' call it Maya or great illusion. As we mistake a coir as a snake, God is taken to be the world under illusion. Mind causes this duality or illusion. Sathya Saibaba has said once, "When you perceive two, then Maya is in action". Hence all of us are under great illusion regarding our separate existence from the rest.
In Mathematics, there is only one number and that is the numeral '1'. The same 1 added up present many different numbers as 2 (1+1), 3(1+1+1) etc. All these are verily God veiled by illusory veils called the thoughts which turn into desires and hatred. Hence, behind this duality, there is really only One, i.e represented by "I". Hence no other description of God will hold good except "I" or I am ". Hence in the Bible, there is a verse, I am That I am!
I have said, Joy and sorrow is only an idea and not real. It is the play of mind. The mind can never survive in Truth since Truth is God. God has no dualities in Him. He is alone and there is no second entity! Hence the feeling of joy and sorrow is mere illusions of the mind!