Psalm 143 - David prays.   He asks God to hear his supplications, his entreaties.  His humble requests include:
  release from judgement ( v2-3);
 relief from his  enemy ( v. 3-4) ;
 Renewed fellowship ( v. 5-7);
Direction and teaching ( v 8,10) ;
Revival of soul and body ( v11-12)

In Daniel 6 we find that Daniel has become an official in the government of Darius.  Other leaders are jealous of Daniel's advancements and plot to destroy him.  They can find no fault in him regarding his job, so they target his  prayer life.  A law is brought to Darius, who signs it without realizing the implications.  No one can pray to anyone except to him, the king, for 30 days.  But Daniel ignores this law and continues his practice of praying 3 times of day before God.  Darius has no choice but to throw Daniel into the lion's den,although he "kept exerting himself to rescue him".
Darius fasts and doesn't sleep that night.  He goes to the lion's den and calls out to Daniel and finds him still alive! God sent his angel to shut the lions' mouths.  But when Darius has the accusers and their families thrown into the den,they don't even reach the bottom before they are crushed to death.
This is enough for Darius to decree that all should fear and tremble before the God of Daniel.  The Living God Who endures forever, Whose Kingdom is everlasting, Who delivers and rescues.

The Shepherd speaks.
David's prayer and Daniel's prayer life are both examples for us.  Daniel 6:10-11 tells us that he kneels 3 times a day, every day.  That he gives thanks, makes petitions and supplications before God. We are not told the content of these prayers, but it is evident in Daniel's life that God honored Daniel's prayers.  V. 3 tells us that even the pagans realized that Daniel "possessed an extraordinary spirit" .  Also " they could find no evidence of corruption, inasmuch as he was faithful and no negligence or corruption was found in him"  The king, Darius, testifies that Daniel served God constantly.  He calls him "Daniel, servant of the living God"  Daniel was thought to be in his 80s at this time.  Yet he was was known for his integrity and faithfulness to the Living God.  Daniel's prayer life had a lot to do with this.
David's prayer life is also significant.  Many of the psalms he wrote are prayers. In Ps. 143 there are specific requests, Ps. 145 is full of praises.  I think Daniel might have prayed David's prayer in 143,
Answer me quickly O Lord, my spirit fails; Do not hide Thy face from me, Lest I become like those who go down to the pit.  Let me hear Thy lovingkindness in the morning; For I trust in Thee;"
Father, like David I pray " Teach me the way in which I should walk; For to Thee I lift up my soul"
"Teach me to do Thy will, For Thou are my God"
From The Imitation of Christ " For a small income a long journey is undertaken; for everlasting life many will scarce once lift a foot from the ground."  and  " But Alas!  for an unchangeable good, for an inestimable reward, for the highest honor,and glory without end, they grudge even the least fatigue."  We are willing to work hard and sacrifice so much for temporary and tiny profit.  But we fail to give our energy and time to Christ , which bears eternal fruit.  Forgive me Lord God.  Change me now! Amen.