Lord, on the day I called for help, you answered me.The Genesis account of creation reminds us, lest we forget, of the closeness that characterized the relationship that existed between God and our first parents. As the origin and sustainer of their existence, the Lord God was not only close to Adam and Eve but also befriended them. The Lord even formed a habit of taking an occasional afternoon stroll in the garden in order to check on them (cf. Genesis 3:8). However, this close relationship took a serious blow when the two were expelled from the garden of Eden on account of their rebellion. And although the Lord remained in relationship with them (and their descendants) even after the rebellion, the relationship became strained. The warmth that had always issued from their closeness to God was replaced with fear (cf. Genesis 3:10), and the ease of approaching God which creatures had heretofore enjoyed slowly faded away. God became an unmoved mover, the dreaded ‘Lord’ with whom a creature could not approach or interact at whim. Even the communication between God and creatures took on a more “official” tone. This is why in the First Reading, we see Abraham, after coming to the realization that he could engage the Lord God in a “casual” conversation as one does with a friend, seized the opportunity to intercede for the inhabitants of the cities of Sodom and Gomorrah. 
As Abraham set to see off the angels of the Lord whom he had graciously welcomed into his home (cf. last Sunday’s First Reading), the Lord, perhaps touched by Abraham’s show of hospitality, decided to reveal to Abraham his plans for Sodom and Gomorrah. Abraham, being the righteous man that he was, could not bear the thought of the innocent inhabitants of the two cities perishing on account of the sins of others. Because of the favor he had found in the eyes of God, Abraham decided to try his luck to see if, for the sake of the innocent souls, he could “talk” God into sparing the two cities. Their friendship notwithstanding, Abraham was aware that what he was about to do was unheard of. Was it possible for a mortal to engage the mighty Lord in a conversation and have him change his mind? Could he, a mere creature, “reason” out with God? Because of what was at stake, Abraham decided to give it a shot. And as it turned out, it was a risk worth taking, for in the course of their conversation, Abraham got to know a side of God that he perhaps didn’t know existed. Abraham realized that the Lord God is not an unmoved mover. He came to know a God who was not only Lord but also a Father; a God who is not a destroyer but a sustainer and nurturer of life. Abraham got to have knowledge of a God who does offer a listening ear when approached with a petition. He came to know that the Lord God does acquiesce to the implorations of his creatures. This is the very teaching that Jesus also imparts to his disciples in the Lord’s Prayer about which we hear in the Gospel reading.
Jesus’ life of ministry was punctuated by prayer. He would always create time and seek quiet places to pray. During those times when he would pray in the presence of his disciples, he must have awed them with the ease and calmness with which he approached prayer. They must have loved Jesus’ manner of praying and secretly wished they were able to pray as he did. When they could not hold it anymore, they approached him and requested him to teach them how to pray. Jesus obliged and taught them what we have come to know as the Lord’s Prayer.
Jesus always addressed his Father as Abba,  dadwhen he prayed. Abba,  dad, is a title of endearment, and Jesus used it when praying because he understood prayer as a casual (as opposed to official) conversation that takes place between an individual and God. During prayer, Jesus, as it were, rushed to God, hugged God, sat on God’s lap, and started to share with God what was in his heart. Jesus was able to be at ease when praying because he was in the presence of his loving dad who was ready to lend him a listening ear. This is the first instruction that he gave his disciples: when you pray, address God as Abba, Father. Perhaps the disciples’ understanding of God, just like ours, had prevented them from approaching God as a loving dad who would put everything aside in order to focus all his attention to this son/daughter of his who had run up to him. Perhaps like us, the disciples had been taught that their relationship to God must remain official in the sense that there are things that they could not tell God. By telling them to approach God as their Abba,  dad, Jesus was telling them that prayer must be a conversation that one has with God. 
Approaching God in prayer as Abba,  dad, sets the tone of the prayer. As Jesus made it clear to the disciples in the two sections that followed the Lord’s Prayer (vv. 5-13), it is when we approach God as Abba, dad, that we can become successful in our prayers. For it is only when we approach God as Abba,  dad, that we can persevere in prayer. As a conversation that one is having with the Lord, prayer will require that one remains at the feet of the Lord for as long as it takes, for a child will come to the father with a list of his/her needs with the conviction that the father is able to provide them. Moreover, a child who is enjoying sitting on the lap of his/her father is never in a hurry to leave.