When should I pray?

Mark 1 - 30 Now Simon's mother-in-law lay sick with a fever, and immediately they told him of her. 31 And he came and took her by the hand and lifted her up, and the fever left her; and she served them. 32 That evening, at sundown, they brought to him all who were sick or possessed with demons. 33 And the whole city was gathered together about the door. 34 And he healed many who were sick with various diseases, and cast out many demons; and he would not permit the demons to speak, because they knew him. 35 And in the morning, a great while before day, he rose and went out to a lonely place, and there he prayed.

Mark 9 - 26 And after crying out and convulsing him terribly, it came out, and the boy was like a corpse; so that most of them said, "He is dead." 27 But Jesus took him by the hand and lifted him up, and he arose. 28 And when he had entered the house, his disciples asked him privately, "Why could we not cast it out?" 29 And he said to them, "This kind cannot be driven out by anything but prayer."

Mark 11 - 25 "And whenever you stand praying, forgive, if you have anything against any one; so that your Father also who is in heaven may forgive you your trespasses. 26 But if you do not forgive men their trespasses, neither will your Father forgive your trespasses."

Luke 2 - 36 And there was a prophetess, Anna, the daughter of Phan'u-el, of the tribe of Asher; she was of a great age, having lived with her husband seven years from her virginity, 37 and as a widow till she was eighty-four. She did not depart from the temple, worshiping with fasting and prayer night and day. 38 And coming up at that very hour she gave thanks to God, and spoke of him to all who were looking for the redemption of Jerusalem.

Luke 3 - 21 Now when all the people were baptized, and when Jesus also had been baptized and was praying, the heaven was opened, 22 and the Holy Spirit descended upon him in bodily form, as a dove, and a voice came from heaven, "Thou art my beloved Son; with thee I am well pleased."

Luke 6 - 27 "But I say to you that hear, Love your enemies, do good to those who hate you, 28 bless those who curse you, pray for those who abuse you.

Luke 18 - 1 And he told them a parable, to the effect that they ought always to pray and not lose heart.

Luke 21 - 34 "But take heed to yourselves lest your hearts be weighed down with dissipation and drunkenness and cares of this life, and that day come upon you suddenly like a snare; 35 for it will come upon all who dwell upon the face of the whole earth. 36 But watch at all times, praying that you may have strength to escape all these things that will take place, and to stand before the Son of man."

Luke 22 - 31 "Simon, Simon, behold, Satan demanded to have you, that he might sift you like wheat, 32 but I have prayed for you that your faith may not fail; and when you have turned again, strengthen your brethren." 33 And he said to him, "Lord, I am ready to go with you to prison and to death." 34 He said, "I tell you, Peter, the cock will not crow this day, until you three times deny that you know me." 35 And he said to them, "When I sent you out with no purse or bag or sandals, did you lack anything?" They said, "Nothing." 36 He said to them, "But now, let him who has a purse take it, and likewise a bag. And let him who has no sword sell his mantle and buy one. 37 For I tell you that this scripture must be fulfilled in me, 'And he was reckoned with transgressors'; for what is written about me has its fulfilment." 38 And they said, "Look, Lord, here are two swords." And he said to them, "It is enough." 39 And he came out, and went, as was his custom, to the Mount of Olives; and the disciples followed him. 40 And when he came to the place he said to them, "Pray that you may not enter into temptation."