Reflecting on the signs of Allah in the universe and the signs (verses) in His Book is a great act of worship which leads to the revival of the heart, an increase in certainty of faith and veneration of the Creator.
The rising and setting of the sun are two great signs of Allah, may He be Exalted, as He says:
{[He is] Lord of the two places of sunrise and Lord of the two places of sunset.
Then which of the favours of your Lord will you deny?}
[Ar-Rahman 55:17, 18].
It is heedlessness for a person not to pay attention to the momentous signs by which he is surrounded, such as the heavens, the mountains, the alternation of night and day, the blowing of the wind and the clouds that are suspended between heaven and earth.
Please see the long answer.