We do need joy, as for this reason we were created by God. But spiritual joy is not same as the joy of this world. True spiritual joy means having a free heart, filled with the peace of Jesus. We have spiritual joy when we free ourselves from the dominion of the enemy, of evil thoughts and temptation
Usually, when it comes about himself, man is always unfair and changes the scale; he is more rightful towards himself, he chooses the better, the biggest, and the most beautiful part: he cries and rejoices for himself more than for others. But, Christ crucified on the Cross the love for oneself, and gave His life for us.