"Pray always without becoming weary"

Jesus told his disciples a parable about the necessity for them to pray always without becoming weary. He said, "There was a judge in a certain town who neither feared God nor respected any human being. And a widow in that town used to come to him and say, 'Render a just decision for me against my adversary.' For a long time the judge was unwilling, but eventually he thought, 'While it is true that I neither fear God nor respect any human being, because this widow keeps bothering me I shall deliver a just decision for her lest she finally come and strike me.'" The Lord said, "Pay attention to what the dishonest judge says.Will not God then secure the rights of his chosen ones who call out to him day and night? Will he be slow to answer them? I tell you, he will see to it that justice is done for them speedily. But when the Son of Man comes, will he find faith on earth? (St Luke 18:1-8) 

What an extraordinary thing it is, the efficiency of prayer! Like a queen, it has access at all times to the Royal presence, and can get whatever it asks for. And it's a mistake to imagine that your prayer won't be answered unless you've something out of a book, some splendid formula of words, specially devised to meet this emergency. If that were true, I'm afraid I should be in a terribly bad position. You see, I recite the Divine Office, with a great sense of unworthiness, but apart from that I can't face the strain of hunting about in books for these splendid prayers-it makes my head spin. There are such a lot of them, each more splendid than the last; how am I to recite them all, or to choose between them? I just do what children have to do before they've learned to read; I tell God what I want quite simply, without any splendid turns of phrase, and somehow he always manages to understand me. For me, prayer means launching out of the heart towards God; it means lifting up one's eyes, quite simply, to heaven, a cry of grateful love, from the crest of joy or the trough of despair; it's a vast, supernatural force which opens out my heart, and binds me close to Jesus. (St Therese of the Child Jesus)