The Key To Happiness Is — To Always Be Grateful To Your Lord For What You Have:
Thanks or Gratitude means reciprocating kindness and giving praise to the one — who has done good and kind things.
The one who is most deserving of Thanks and praise From people is Allah(swt) because of the great Favours and blessings that He has bestowed upon His slaves in both spiritual and worldly terms.
Shukr means to acknowledge and openly show appreciation For a blessing, kufr is the exact opposite.
Kufr is derived From the root word kafara, which means to cover something and make it hidden.
In this context, kufr means to refuse to appreciate these benefits, thus hiding one’s appreciation and not openly showing gratitude. Those who are ungrateful are ultimately labeled with disbelief (kufr), illustrating the magnitude of being ungrateful to Allah.
…And whoever commits a good deed, We will increase For him good therein. Indeed, Allah is Forgiving and Appreciative (Shakūr). (42:23)
“And surely, We gave you authority on the earth and appointed For you therein provisions (For your life). Little thanks do you give.” (Al-A`raf 7:10)
“And among His Signs is this, that He sends the winds as glad tidings, giving you a taste of His Mercy (i.e. rain), and that the ships may sail at His Command, and that you may seek of His Bounty, in order that you may be thankful.”
(Luqman 31:46)
It was narrated From Mu'adh ibn Jabal that the Messenger of Allah (saw) took his hand and said: “O Mu’adh, by Allah I love you, by Allah I love you.” Then he said, “I advise you, O Mu’adh, do not Fail Following every prayer to say: O Allah help me to remember You, thank You and worship You properly.” (Narrated by Abu Dawud and al-Nasai).
Gratitude For Blessings is a cause of them being increased.
Allah says:“And (remember) when your Lord proclaimed: ‘If you give thanks (by accepting Faith and worshipping none but Allah), I will give you more (of My blessings); but if you are thankless (i.e. disbelievers), verily, My punishment is indeed severe’.” (Ibrahim 14:7)
Gratitude of the heart — what is meant is that the heart senses the value of the blessings that Allah has bestowed upon His slave, and Fully acknowledges that the One Who has bestowed these Great Blessings is Allah Alone, with no partner or associate.
Allah says:“And whatever of blessings and good things you have, it is From Allah.” (An-Nahl 16:53)
Abū al-Dardā(May Allah be pleased with him)once said, “He who does not know the blessings that Allah has conferred upon him except in his Food or drink, then he indeed has little knowledge, and his punishment is hastened.”
Ibn al-Qayyim (May Allah have mercy on him) said:“Gratitude may be in the heart, in submission and humility; on the tongue, in praise and acknowledgement; and in the physical Faculties, by means of Obedience and Submission.” (Madarij al-Salikin (2/246)
Moreover, Thankfulness [Shukr] can be subdivided into several categories, namely:
1. Thankfulness expressed by the tongue [shukr bi’l-lisan] — This constitutes the acknowledgment of the benefaction [ni’ma] with an attitude of humble acceptance [istikana].
2. Thankfulness expressed by the body and the limbs [shukr bi’l-badan wa ‘l – arkan] — This is the characteristic indication of loyalty and readiness to serve [al-wafa’ wa ‘l-khidma].
3. Thankfulness expressed by the inner Feeling [shukr bi’l-qalb] — This requires a careful balance between the visible display of appreciation and the constant preservation of a sense of reverence.
It has also been said that thankfulness of the eyes [shukr al-‘ainain] means that you overlook any Fault you notice in your companion, while thankfulness of the ears [shukr al-udhunain] means that you ignore any fault you hear him accused of possessing.
In the simplest terms, thankfulness [shukr] means that you do not disobey Allah (swt) by misusing His gracious Favors.
So,the point is that — when a person remains Grateful to his Lord, i.e. he uses the Lord's Blessings according to His will, then he remains happy and satisfied because True happiness is in Obedience to his Lord.
May Allah(swt) include us among His Grateful Servants.(Ameen).
JazakAllah (May Allah reward you with goodness) For reading.