God has legislative and genetic plans for educating the soul of people and has included difficulties in both plans. The legislative plan elaborates worships and the genetic plan involves difficulties aimed at testing people and ultimately educating and developing them. Prayer, fasting, Hajj, Jihad and hypocrisy are difficulties that come with obligations and patience and resistance in doing them leads to development of transcendental talents. On the other hand hunger, fear and finical as well as human costs are among difficulties included in the genetic plan, are imperative and educate people.
What is piety? To control ourselves in rage and in passion
The term for piety (Taqwa) is derived from (waqi, yaqi) meaning "to protect/control oneself" and safeguarding. One must be able to control oneself; for example he must not see attractive but prohibited scenes. Some voices are so repulsive that not listening to them is not an important feat, such as the voice of some animals, but sometimes beautiful sounds are prohibited. In this case not listening to them is valuable. If we are told that someone has vowed to give us 70 thousand tomans, we would be happy, but sometimes we resort to every trickery not to pay 70 thousand tomans Quint (one-fifth of the surplus annual income to be paid as religious tax). This is not the way of a believer, and he is always mindful of God’s satisfaction.
If we say our prayers on time, a prayer that “prohibits immorality and wrongdoing, and the remembrance of Allah is greater, And Allah knows that which you do,”‌ it would affect us and prevent us from committing sin.
To say prayers on time is a great trial. A believer is mindful of God’s satisfaction, and God loves timely prayer. Imam Reza says, “Always say your prayers on time.”‌

Source: tebyan