According to search-discovered classical Islamic scholarship, Shukr (gratitude) is a foundational act of worship and a defining characteristic of a believer, far exceeding a simple verbal 'thank you'. Ibn Qayyim al-Jawziyya provides a comprehensive framework, explaining that true Shukr is manifested in three interconnected ways: with the heart (al-qalb), through recognizing and feeling humility for Allah's blessings; with the tongue (al-lisān), through praise and acknowledgement like saying 'Alhamdulillah'; and with the limbs (al-jawāriḥ), by using Allah's favors in obedience to Him and for the benefit of creation. This understanding is reinforced by Imam Al-Ghazali, who emphasized that the highest form of gratitude is finding joy in blessings because they are a means to draw closer to the Bestower, Allah Himself. The Quran establishes a divine law in Surah Ibrahim (14:7): 'If you are grateful, I will surely increase you [in favor].' This promise transforms Shukr from a mere virtue into a direct cause for receiving more blessings, both spiritual and worldly, making it an essential pillar of a Muslim's faith and daily practice.