Among other things, four things are clearly rewarded in Scriptures as stated by the Lord Jesus in the Sermon on the Mount recorded in Matthew 6. They are:

1. Giving. Matthew 6:4
2. Prayer. Matthew 6:6
3. Fasting. Matthew 6:18
4. Kingdom Stewardship! It is your stewardship that God rewards. Matt 6:33, “But seek ye first the kingdom of God, and his righteousness; and all these things shall be added unto you.” (BWE) “‘Work first for God’s kingdom and what he calls good. Then you will have all these things also.”

Let us look at prayers.
Matthew 6:6, “But thou, when thou prayest, enter into thy closet, and when thou hast shut thy door, pray to thy Father which is in secret; and thy Father which seeth in secret shall reward thee openly.”

Facts
1. Your private prayer determines your public reward. Your father who sees in secret shall reward you openly.
2. Prayer is your access to divine power for accomplishing any meaningful results on earth.
3. Your accuracy and determination in prayer is rewarded with accumulation of things. “Therefore I say unto you, What things soever ye desire, when ye pray, believe that ye receive them, and ye shall have them.” Mark 11:24. So then prayer is one avenue through which you accumulate things!
4. You stop your adversaries dead on their track through corrosive and abrasive Spirit-inspired prayers! Esther reversed a death sentence passed on a whole nation of the Jews through three days of deep praying!
5. You can reverse defeat and failure through tenacious and persistent prayer. You cannot win the battles of life in the court of sympathy or public opinion but in the place of private supplication. If all you know is complain and cry, you will remain defeated and frustrated. The only way to put an end to frustration is supplication! You can change seasons through prayer.
6. It is through prayer you obtain answers to difficult and complicated problems! Daniel 2:21-23
7. All unfruitfulness can be terminated through prayer. Isaac terminated 20 years of barrenness through effective prayer! Genesis 25:21, “And Isaac intreated the LORD for his wife, because she was barren: and the LORD was intreated of him, and Rebekah his wife conceived.”

Here are some of the benefits:
1. Breaking the back of poverty
2. Freedom from sickness and disease
3. Complete deliverance from satanic afflictions
4. Marital success
5. Business success
6. A great job
7. Termination of barrenness

Does The Length Of Prayer Matter?
Yes and no. No because without faith, length of prayer does not matter. Yes because Jesus prayed long hours. The longer you tarry in his presence, the more his glory robs off on you, the more power you generate and the more anointing you can access. Mercy comes when you are in his presence. You receive more grace to help in the time of need.

In summary:
Great living comes from great praying! Prevailing prayer is the corner stone of a successful life. Unless you fight, you may have no access to your breakthrough. Warfare prayer and fasting ensure that burdens are lifted, obstacles are demolished, yokes destroyed and that your access to your breakthrough is guaranteed. Your tests become testimonies when you pray!