Human beings more than anything else need friendship. Young or old, male or female we all yearn for that companionship. As brilliantly and succinctly put by a wise Talmudic sage, "Either friendship or death".
In order to explain the diverse range of festivals during this month of Tishrei, a beautiful metaphor is offered by the first Lubavitcher Rebbe.
Once, a father showed tremendous kindness to his child. Unfortunately the child grew to become ungrateful. After some consideration the father decided to withdrew his generosity of spirit which naturally caused the child great distress. Upon some reflection the wise child realised that the reason behind his father's "hiding his face”, was in fact because he wanted his child to "seek him out" and to reconnect with him on a deeper and more meaningful level.
This says Rabbi Shneur Zalman is the meaning behind the Days of Awe on the one hand and the Days of Joy on the other hand. Rosh Hashana and Yom Kippur represent the moment when our father in heaven hides from his children, causing us the Jewish people to seek him out. Eventually the child rediscovers the father who in turn embraces his son unreservedly and they both rejoice in each other's company. This coming together of G-d and the Jewish people is played out during the festive and joyous moments of Sukkot and Simchat Torah.
There are two powerful lessons we can learn from this metaphor. Firstly, we learn that just as when a father "hides" from his child, it is not because he is angry or malicious, it is only that he wants his child to be more appreciative of the things he has. So too does this apply in the relationship between the Jewish people and G-d.
Secondly, we learn that the highlight of the series of festivals during this month of Tishrei, are in fact the days of joy. The days of awe, are only a prelude to this special moment of pure joy and happiness as father and child embrace.
Let us always remember that the ultimate defining character of the relationship between the Jewish people and G-d is not of a G-d who is hiding from his children but a G-d who embraces his children without any reservation.