When we understand our relationship with God then we all will be happy. It is an essential factor for establishing peace in the world.
One who is ignorant of scientific knowledge of the spirit soul does not look inside the body to find happiness in the soul; instead, he goes outside to search for happiness
Srimad bhagavatam 7.13.29,
One has to learn tolerance in the face of dualities such as happiness and distress, or cold and warmth, and by tolerating such dualities become free from anxieties regarding gain and loss.
Bhagavad Gita 2.45,
The spirit soul can be happy only in the association of the supreme living being, the Personality of Godhead, and nowhere else.
Srimad Bhagavatam 3.2.11,
The more we are happy in Krishna Consciousness the more we become purified.
Without the grace of the Lord, no one can become happy and prosperous.
Srimad Bhagavatam 3.1.26,