From: Mark 1:29-39
The Curing of Peter's Mother-In-Law
 And immediately He (Jesus) left the synagogue, and entered the house of Simon and Andrew, with James and John.  Now Simon's mother-in-law lay sick with a fever, and immediately they told Him of her.  And He came and took her by the hand and lifted her up, and the fever left her; and she served them.
Jesus Cures Many Sick People
 That evening, at sundown, they brought to Him all who were sick or possessed with demons.  And the whole city was gathered together about the door.  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.
Jesus Goes To a Lonely Place To Pray
 And in the morning, a great while before day, He rose and went out to a lonely place, and there He prayed.  And Simon and those who were with Him followed Him,  and they found Him and said to Him, "Everyone is searching for you."  And He said to them, "Let us go on to the next towns, that I may preach there also; for that is why I came out."  And He went throughout all Galilee, preaching in their synagogues and casting out demons.
34. Demons possess a supernatural type of knowledge and therefore they recognize Jesus as the Messiah (Mark 1:24). Through the people they possess they are able to publish this fact. But Our Lord, using His divine powers, orders them to be silent. On other occasions He also silences His disciples (Mark 8:30; 9:9), and He instructs people whom He has cured not to talk about their cure (Mark 1:4; 5:43; 7:36; 8:26). He may have acted in this way to educate the people away from a too human and political idea of the Messiah (Matthew 9:30). Therefore, He first awakens their interest by performing miracles and gradually, through His preaching, gives them a clearer understanding of the kindof Messiah He is.
Some Fathers of the Church point out that Jesus does not want to accept, in support of the truth, the testimony of him who is the father of lies.
35. Many passages of the New Testament make reference to Jesus praying. The evangelists point to Him praying only on specially important occasions during His public ministry: Baptism (Luke 3:1), the choosing of the Twelve (Luke 6:12), the first multiplication of the loaves (Mark 6:46), the Transfiguration (Luke 9:29), in the garden of Gethsemane prior to His passion (Matthew 26:39) etc. Mark for his part, refers to Jesus' prayer at three solemn moments: at the beginning of His public ministry (1:35), in the middle of it (6:46), and at the end, in Gethsemane (14:32).
Jesus' prayer is prayer of perfect praise to the Father; it is prayer of petition for Himself and for us; and it also a model for His disciples. It is a prayer of perfect praise and thanksgiving because He is God's beloved Son in whom the Father is well pleased (cf. Mark 1:11). It is a prayer of petition because the first spontaneous movement of a soul who recognizes God as Father is to ask Him for things. Jesus' prayer, as we see in very many passages (e.g. John 17:9ff) was a continuous petition to the Father for the work of redemption which He, Jesus, had to achieve through prayer and sacrifice.
Our Lord wants to give us an example of the kind of attitude a Christian should have; he should make a habit of addressing God as son to Father in the midst of and through his everyday activities--work, family life, personal relationships, apostolate--so as to give his life a genuinely Christian meaning, for, as Jesus will point out later on, "apart from Me you can do nothing" (John 15:5).
"You write: `To pray is to talk with God. But about what?' About what? About Him, about yourself: joys, sorrows, successes and failures, noble ambitions, daily worries, weaknesses! And acts of thanksgiving and petitions: and love and reparation. In a word: to get to know Him and to get to know yourself: `to get acquainted!'" ([St] J. Escriva, "The Way").
38. Jesus tells us here that His mission is to preach, to spread the Good News. He was sent for this purpose (Luke 4:43). The Apostles, in turn, were chosen by Jesus to be preachers (Mark 3:14; 16:15). Preaching is the method selected by God to effect salvation: "it pleased God through the folly of what we preach to save those who believe" (1 Corinthians 1:21). This is why St. Paul says to Timothy: "Preach the word, be urgent in season and out of season, convince, rebuke, and exhort, be unfailing in patience and teaching" (2 Timothy 4:1-2). Faith comes from hearing, we are told in Romans 10:17, where St. Paul enthusiastically quotes Isaiah: "How beautiful are the feet of those who preach good news!" (Romans 10:15; Isaiah 52:7).
The Church identifies preaching the Gospel as one of the main tasks of bishops and priests. St. Pius X went so far as saying that "for a priest there is no duty more grave or obligation more binding (to dispel ignorance)" ("Acerbo Nimis"). In this connection Vatican II states: "The people of God is formed into one in the first place by the Word of the living God (cf. 1 Peter 1:23; Acts 6:7; 12:24), which is quite rightly sought from the mouths of priests (2 Corinthians 11:7).
For since nobody can be saved who has not first believed (Mark 16:16), it is the first task of priests as co-workers of the bishops to preach the Gospel of God to all men (2 Corinthians 11:7). In this way they carry out the Lord's command `Go into all the world and preach the Gospel to every creature' (Mark 16:15) (cf. Malachi 2:7; 1 Timothy 4:11-13; etc.) and thus set up and increase the people of God" ("Presbyterorum Ordinis").
Jesus' preaching is not just limited to words: He backs up His teaching with His authority and with deeds. The Church also has been sent to preach salvation and to effect the work of salvation which it proclaims--a work done through the Sacraments and especially through the renewal of the sacrifice of Calvary in the Mass (Vatican II, "Sacrosanctum Concilium", 6).
In the Church of God all of us should listen devoutly to the preaching of the Gospel and we all should feel a responsibility to spread the Gospel by our words and actions. It is the responsibility of the hierarchy of the Church to teach the Gospel authentically--on the authority of Christ.
Source: "The Navarre Bible: Text and Commentaries". Biblical text taken from the Revised Standard Version and New Vulgate. Commentaries made by members of the Faculty of Theology of the University of Navarre, Spain. Published by Four Courts Press, Kill Lane, Blackrock, Co. Dublin, Ireland. Reprinted with permission from Four Courts Press and Scepter Publishers, the U.S. publisher.