Rav Sadya Gaon: Every matter has a prepared time and an order.

Rashi: For everything that man does like he desires and transgresses the creed, there is a prepared time for punishment.

Ibn Ezra: A Chacham knows that everything has its time, so he will not fight a man who is succeeding.

Rashbam: Every desire of Hashem has a time for judgment.

Ri Kara: Hashem judges a person for every act that he does, good or bad, to pay him according to his ways.

Rid: A Chacham knows the time of everything, and conducts a matter according to its time and law.

Seforno: For every Mitzvah that Hashem desired to command, there is a proper time and reason for it.

Metzudas David: Every Chefetz (desire of the king) and Mishpat (etiquette of the kingdom), there is a time to follow them.

Rav Sadya Gaon: Man's affliction is great, for "he does not know what will come from the matters, and there is no one to tell him" (7).

Rashi: Man's time for punishment is when his measure of evil is full and overflowing. Here, "Ki" means when, like "Ki Yihyeh Lahem Davar Ba Elai" (Shemos 18:16).

Ibn Ezra: Even though he knows that everything has its time, he does not know when the time is. This is a great evil!

Rashbam: Man's evil is great on himself; Hashem pays to him his 'reward'.

Ri Kara: Man has ¹ many sins. Therefore, he should be careful in all his ways, lest they punish him from above for his sins.

Rid: This refers to "Ani Pi Melech Shemor" (2). I command you so, for man's evil is great on him, for "he does not know what will come upon him, and who will tell him [before it comes]?!" (7).

Seforno: Man's Yetzer ha'Ra entices him greatly to sin, so Hashem needed to enact Mitzvos to save him from his evil.

Metzudas David: When man thinks ² deeply, he will understand when to follow the king's command and the etiquette of the kingdom.