Have you ever wondered what is it? Is it a mood, a delusion, a state of mind or a way of life? What makes us happy? Does happiness actually exist in this world?
In the Qur’ân, Allâh mentions happiness several times. For instance, the All-Mighty says: “Indeed the companions of Paradise, that Day [Day of Judgement], will be amused in [joyful] occupation.”  and “Enjoying what their Lord has given them, and their Lord protected them from the punishment of Hellfire.” 
When Allâh mentions utter and complete happiness, He talks about the happiness of the next life. However, what about the happiness of this life?
You can find several ahadîth in the authenticated Sunnah and âyât from the Qur’ân which encounter happiness in this life – and we can learn a lot from them!
What do we need to be happy?
This question bothers humankind since the creation of man. Innumerable philosophers, psychologists, artists, poets and lyricists have tried to answer this question – and failed. Not a single one of them was able to develop an accurate and complete model of happiness. The most commonly known model is Maslow’s hierarchy of needs. It basically claims that our needs are
1. Physiological (sleep, food, air, water, etc)
2. Safety (shelter, financial security, health, etc)
3. Love/belonging (community, family)
6. Self-transcendence (religion)
Looks quiet logical, right? Maslow, however, claims that you can only gain happiness and contentment from faith or spirituality if all other needs are met. Is this what we believe in?
To answer this question, we look at the noble Qur’ân. Allâh tells us the story about Prophet Ibrâhîm who sent his wife Hâjar and his son Ismâ’îl to a remote place in the desert where the Kâ’ba was built later on. When he left, he made a profound du’â: “Our Lord, I have settled some of my descendants in an uncultivated valley near Your sacred House, our Lord, that they may establish prayer. So make hearts among the people incline toward them and provide for them from the fruits that they might be grateful.” From this meaningful du’â we can derive that our needs are
If you compare it with Maslow’s hierarchy of needs, it is, indeed, exactly the other way around!
We can find the same meanings in the Sunnah.
Fadalah bin 'Ubaid Al-Ansari reported: I heard the Messenger of Allah صلى الله عليه وسلم say: “Happiness is due to him who is guided to Islam and possesses provision that suffices him for his day and remains content.” 
Narrated Al-Miqdad ibn al-Aswad: I swear by Allah, I heard the Messenger of Allah صلى الله عليه وسلم say: “The happy man is he who avoids dissensions: happy is the man who avoids dissensions; happy is the man who avoids dissensions: but how fine is the man who is afflicted and shows endurance.” 
Nafi' ibn 'Abdu'l-Harith reported that the Prophet said, "Part of the happiness of the Muslim man includes a spacious dwelling, righteous neighbour and a good mount" 
Therefore, we can raise or lower the level of our own happiness depending on our faith and deeds.
Are religious people really happier?
Studies have found that religious people tend to be happier than non-religious people. Moreover, the happiness of non-religious people tends to be transient while the happiness of religious people tends to be enduring. How amazing is that!
My assumption is that religious people believe that each and everything that happens in our life has a meaning – and which religion gives more meaning to life, trials and tribulations than Islam?
The ultimate meaning of trials is to bring us closer to Allâh. Therefore, while you go through a tough time, you come closer to Allâh. And when ease comes after that hardship, you find yourself closer to Allâh than before!
This is exactly what you can observe around yourself. Some sisters and brothers go through unimaginable pain, through seemingly unbearable trials. Some of these sisters and brothers are dazzling patient – and, therefore, Allâh places happiness into their hearts.
What to do?
The very most important step to happiness is prayer. We have seen the evidence for this statement in the prayer of Prophet Ibrâhîm. It gives you the opportunity to experience moments without a care in the world. Put your trust in Allâh. We can read in the Qur’ân: “No disaster strikes upon the earth or among yourselves except that it is in a register before We bring it into being - indeed that, for Allah , is easy” 
Stay away from prohibited deeds. “And whatever strikes you of disaster - it is for what your hands have earned; but He pardons much.”  This âyah warns us of the evil consequences and punishments for the evil that we ourselves may have done.
Be optimistic – even in the darkest moment. You may know all ahadîth and âyât like “For indeed, with hardship [will be] ease.”  and “And the Hereafter is better for you than the first [life]. And your Lord is going to give you, and you will be satisfied.”  But “knowing in mind” does not equal “knowing in heart”. Internalize these ahadîth and âyât. You can write them on a paper which you carry with you to read every now and then. You can appoint a specified time every day to ponder over them. Whatever - make sure you really internalize these promises!
Be grateful – even for the smallest thing. Even the sight of a butterfly, the fresh breeze of the morning air just before the sun rises, the blessing of being able to stand in prayer and touch the ground with your face directly... these are all tremendous blessings of our Lord!
Help others. “So as for the orphan, do not oppress [him]. And as for the petitioner, do not repel [him].”  Allâh asks us to help others – especially when we are not fine ourselves. We will often find others who are far worse off than we are. And they are those who we should compare ourselves with in this world. Abu Hurairah reported: The Messenger of Allah صلى الله عليه وسلم said, "Look at those who are inferior to you and do not look at those who are superior to you, for this will keep you from belittling Allah's Favour to you."
Last but definitely not least: When you are happy, do not forget or even refuse to do sajdah and thank Allâh for all what He has given you – where you are nearest to Him! It was narrated from Abu Bakrah that when the Prophet صلى الله عليه وسلم heard news that made him happy, or for which one should be happy, he would fall down prostrate in gratitude to Allah, the Blessed and Exalted. 
 Qur’ân 36: 55
 Qur’ân 52: 18
 Riyad as-Sâlihîn, Book 1, Hadîth 513; graded: hasan sahîh
 Sunan Abi Dawud, Hadîth 4263; graded: sahîh
 Al-Adab Al-Mufrad, Hadîth 116; graded: sahîh li ghayrih
 Qur’ân 57: 22
 Qur’ân 42: 30
 Qur’ân 94: 5 & 6
 Qur’ân 93: 4-5
 Qur’ân 93: 8-9
 Sunan ibn Mâjah, Vol. 1, Book 5, Hadîth 1394; graded: hasan