And Who has measured; and then guided.
Mujahid said,
"He guided man to distress and happiness, and he guided the cattle to their pastures."
This Ayah is similar to what Allah has said about Musa's statement to Fir`awn,
رَبُّنَا الَّذِى أَعْطَى كُلَّ شَىءٍ خَلْقَهُ ثُمَّ هَدَى
Our Lord is He Who gave to each thing its form and nature, then guided it aright. (20;50)
meaning, He decreed a set measure and guided the creation to it.
This is just as is confirmed in Sahih Muslim on the authority of Abdullah bin `Amr that the Messenger of Allah said,
إِنَّ اللهَ قَدَّرَ مَقَادِيرَ الْخَلَيِقِ قَبْلَ أَنْ يَخْلُقَ السَّمَواتِ وَالاَْرْضَ بِخَمْسِينَ أَلْفَ سَنَةٍ وَكَانَ عَرْشُهُ عَلَى الْمَاء
Verily, Allah ordained the measure of all creation fifty thousand years before He created the heavens and the earth, and His Throne was over the water.
Concerning Allah's statement,
وَالَّذِي أَخْرَجَ الْمَرْعَى