Ibn Abbas relates that the Messenger of Allah ﷺ said, “Reflect deeply upon the creation, but do not reflect upon the essence of the Creator. Verily, his essence cannot be known other than to believe in it.”
(Musnad al-Rabi’)
Another hadith reported by Ibn Umar on the authority of al-Mu’jam al-Awsat also reports the same with slight difference in words. Ibn Umar relates that the Messenger of Allah ﷺ said, “Reflect deeply upon the blessings of Allah, but do not reflect upon the essence of Allah.” Al-Albani has graded both the ahadith as hasan (fair).
Reflection upon the creation of Allah or the blessings of Allah is the same. Here the Messenger of Allah ﷺ enjoins the believers to reflect upon whatsoever Allah has blessed them with in their body as well as in the universe. When we brood over the various vital organs of our body, how they function and how they make us the best creation in the world; how the child grows in the various stages of life; how Allah gives us sustenance to live; how He guides us to the way of life He likes; how Allah changes the day into the night, and the night into the day; how the wind blows; how the sun rises and sets; how the moon rises and wanes; how the various stars, galaxies and planets move in the vast universe; how Allah has held the sky without any columns, etc., we feel compelled to praise Allah for His bounties, and do research in the various fields.