Deliberative speeches were often given in the assembly as orators would debate the course a polis should steer. Judicial speeches were given in the courts as orators (serving the function of lawyers) would present their case and try to sway the judges. Epideictic speeches were given on public occasions and would include the praise of some subject, either a city, country, or person.
All three genres of rhetoric can be found in the New Testament, and no book can be classified as just one or the other. No book of the NT was an ancient speech, at least not in the rhetorical sense. The gospels and Acts are narratives, the Pauline books are all letters. Yet, they were meant to be read aloud and thus, they carry many elements from rhetorical theory. Small sections of different NT books can be considered to fall into one or another of these three genres of rhetoric.
A good example of deliberative oratory in the New Testament is the Sermon on the Mount and its parallel, the Sermon on the Plain. The audience of these passages is supposed to deliberate about things of the future, namely, how to live their lives. The following is a good illustrative section from the Sermon on the Mount (All quotes NRSV):
Matt. 6:25 “Therefore I tell you, do not worry about your life, what you will eat or what you will drink, or about your body, what you will wear. Is not life more than food, and the body more than clothing? 26 Look at the birds of the air; they neither sow nor reap nor gather into barns, and yet your heavenly Father feeds them. Are you not of more value than they? 27 And can any of you by worrying add a single hour to your span of life? 28 And why do you worry about clothing? Consider the lilies of the field, how they grow; they neither toil nor spin, 29 yet I tell you, even Solomon in all his glory was not clothed like one of these. 30 But if God so clothes the grass of the field, which is alive today and tomorrow is thrown into the oven, will he not much more clothe you—you of little faith? 31 Therefore do not worry, saying, ‘What will we eat?’ or ‘What will we drink?’ or ‘What will we wear?’ 32 For it is the Gentiles who strive for all these things; and indeed your heavenly Father knows that you need all these things. 33 But strive first for the kingdom of God and his righteousness, and all these things will be given to you as well. 34 “So do not worry about tomorrow, for tomorrow will bring worries of its own. Today’s trouble is enough for today.A good example of Judicial oratory comes from the defense speeches in Acts. Paul goes through several trials before being delivered to Rome. During these trials there are examples of more or less complete forensic speeches on the part of both the accuser (prosecuting attorney) and Paul (the defendant/defense attorney). The following passage from Acts 24 demonstrates one of Paul's defense speeches:
Acts 24:10 When the governor motioned to him to speak, Paul replied: ¶ “I cheerfully make my defense, knowing that for many years you have been a judge over this nation. 11 As you can find out, it is not more than twelve days since I went up to worship in Jerusalem. 12 They did not find me disputing with anyone in the temple or stirring up a crowd either in the synagogues or throughout the city. 13 Neither can they prove to you the charge that they now bring against me. 14 But this I admit to you, that according to the Way, which they call a sect, I worship the God of our ancestors, believing everything laid down according to the law or written in the prophets. 15 I have a hope in God—a hope that they themselves also accept—that there will be a resurrection of both the righteous and the unrighteous. 16 Therefore I do my best always to have a clear conscience toward God and all people. 17 Now after some years I came to bring alms to my nation and to offer sacrifices. 18 While I was doing this, they found me in the temple, completing the rite of purification, without any crowd or disturbance. 19 But there were some Jews from Asia—they ought to be here before you to make an accusation, if they have anything against me. 20 Or let these men here tell what crime they had found when I stood before the council, 21 unless it was this one sentence that I called out while standing before them, ‘It is about the resurrection of the dead that I am on trial before you today.’Finally, a good example of epideictic oratory can be seen in Paul's praise of agape in 1 Corinthians 13.
1Cor. 13:4 Love is patient; love is kind; love is not envious or boastful or arrogant 5 or rude. It does not insist on its own way; it is not irritable or resentful; 6 it does not rejoice in wrongdoing, but rejoices in the truth. 7 It bears all things, believes all things, hopes all things, endures all things. 8 Love never ends. But as for prophecies, they will come to an end; as for tongues, they will cease; as for knowledge, it will come to an end. 9 For we know only in part, and we prophesy only in part; 10 but when the complete comes, the partial will come to an end. 11 When I was a child, I spoke like a child, I thought like a child, I reasoned like a child; when I became an adult, I put an end to childish ways. 12 For now we see in a mirror, dimly, but then we will see face to face. Now I know only in part; then I will know fully, even as I have been fully known. 13 And now faith, hope, and love abide, these three; and the greatest of these is love.Knowing what genre of rhetoric a certain passage falls into can help the critic make interpretive decisions about what the audience would expect and how well the text is able to persuade according to the goal of each genre.