I always thought that man was the greatest creation, but Allaah says that if we think that we were hard to create, then we should look at the heavens; are the heavens a greater creation than man?

All perfect praise be to Allaah, The Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad, sallallaahu ʻalayhi wa sallam, is His slave and Messenger. 

The heavens are bigger and greater creation than man in terms of size; Allaah, The Exalted, says (what means): {The creation of the heavens and earth is greater than the creation of mankind, but most of the people do not know.} [Quran 40:57]

Ibn Katheer commented on this verse saying, "Allaah tells us that He will bring back His creation on the Day of Resurrection, and that is easy for Him because He created the heavens and the earth, and creating them is greater than creating mankind, both the first time and when He creates them again. The One Who is able to do that is able to do anything that is less than that for a greater reason."

However, man is better than the heavens and the earth. Allaah has favored man with intellect, knowledge, and the responsibility of bearing the trust that the heavens and the earth refused to bear; Allaah, The Exalted, says (what means): {And We have certainly honored the children of Adam and carried them on the land and sea and provided for them of the good things and preferred them over much of what We have created, with (definite) preference.} [Quran 17:70] He also says (what means): {Indeed, we offered the Trust to the heavens and the earth and the mountains, and they declined to bear it and feared it; but man (undertook to) bear it. Indeed, he was unjust and ignorant.} [Quran 33:72]

Allaah knows best.