Matthew 6:5-13: "5 'And when you pray, you must not be like the hypocrites. For they love to stand and pray in the synagogues and at the street corners, that they may be seen by others. Truly, I say to you, they have received their reward. 6 But when you pray, go into your room and shut the door and pray to your Father who is in secret. And your Father who sees in secret will reward you.
"7 'And when you pray, do not heap up empty phrases as the Gentiles do, for they think that they will be heard for their many words. 8 Do not be like them, for your Father knows what you need before you ask him. 9 Pray then like this: Our Father in heaven, hallowed be your name. 10 Your kingdom come, your will be done, on earth as it is in heaven. 11 Give us this day our daily bread, 12 and forgive us our debts, as we also have forgiven our debtors. 13 And lead us not into temptation, but deliver us from evil.'"
Matthew 7:7-11: "7 'Ask, and it will be given to you; seek, and you will find; knock, and it will be opened to you. 8 For everyone who asks receives, and the one who seeks finds, and to the one who knocks it will be opened. 9 Or which one of you, if his son asks him for bread, will give him a stone? 10 Or if he asks for a fish, will give him a serpent? 11 If you then, who are evil, know how to give good gifts to your children, how much more will your Father who is in heaven give good things to those who ask him!'"
Luke 11:5-13: "5 And he said to them, 'Which of you who has a friend will go to him at midnight and say to him, "Friend, lend me three loaves, 6 for a friend of mine has arrived on a journey, and I have nothing to set before him"; 7 and he will answer from within, "Do not bother me; the door is now shut, and my children are with me in bed. I cannot get up and give you anything"? 8 I tell you, though he will not get up and give him anything because he is his friend, yet because of his impudence he will rise and give him whatever he need. 9 And I tell you, ask, and it will be given to you; seek, and you will find; knock, and it will be opened to you. 10 For everyone who asks receives, and the one who seeks finds, and to the one who knocks it will be opened. 11 What father among you, if his son asks for a fish, will instead of a fish give him a serpent; 12 or if he asks for an egg, will give him a scorpion? 13 If you then, who are evil, know how to give good gifts to your children, how much more will the heavenly Father give the Holy Spirit to those who ask him!'"
Hebrews 4:16: "Let us then with confidence draw near to the throne of grace, that we may receive mercy and find grace to help in time of need."
+++
The text is public domain:
1 Come, my soul, with ev'ry care,Jesus loves to answer prayer;He Himself has bid thee pray,Therefore will not turn away.2 Thou art coming to a King,Large petitions with thee bring;For His grace and pow'r are suchNone can ever ask too much.3 With my burden I begin:Lord, remove this load of sin;Let Thy blood, for sinners spilt,Set my conscience free from guilt.4 Lord, Thy rest to me impart,Take possession of my heart;There Thy blood-bought right maintainAnd without a rival reign.5 While I am a pilgrim here,Let Thy love my spirit cheer;As my guide, my guard, my friend,Lead me to my journey's end.6 Show me what is mine to do;Ev'ry hour my strength renew.Let me live a life of faith;Let me die Thy people's death.
+++
The passage from Matthew 6 is alluded to in the line "He Himself has bid thee pray" in the first verse.
The passages from Matthew 7 and Luke 11 (specifically the parts about asking) may also be included in "He Himself has bid thee pray," but they also seem to be referred to at the end of the second verse: "His grace and pow'r are such / None can ever ask too much."
"The throne of grace" from Hebrews 4:16 seems to be the basis for the line "Thou art coming to a King" in the second verse. The confidence and grace in the passage also appear more generally in the first three verses.
The line "Lord, Thy rest to me impart" at the beginning of the fourth verse may refer to Matthew 11:28: "'Come to me, all who labor and are heavy laden, and I will give you rest.'"
