The Biblical record tells us that election has been a fact from the beginning. Adam was chosen to be the representative, the federal head, of all mankind in the Garden of Eden. Also, Noah, Abraham, Moses, et. al. were chosen by God. Paul writes regarding Jacob and Esau (Romans 9:11-12), "though they were not yet born and had done nothing either good or bad--in order that God's purpose of election might continue, not because of works but because of his call-- she was told, 'The older will serve the younger.'"
But election in terms of the decree is more than election to service or representation. This election is election to eternal life and salvation, as indicated in Romans 8:29-30, cited earlier, where predestination leads to glory. Peter speaks of this in his epistle when he refers to his readers (1 Peter 1:1-2) as those "who are elect exiles of the dispersion in Pontus, Galatia, Cappadocia, Asia, and Bithynia, according to the foreknowledge of God the Father." Paul likewise refers to believers as chosen in Colossians 3:12 "Put on then, as God's chosen ones, holy and beloved, compassion, kindness, humility, meekness, and patience." That this choosing is eternal is expressed in 2 Thessalonians 2:13: "But we should always give thanks to God for you, brethren beloved by the Lord, because God has chosen you from the beginning for salvation through sanctification by the Spirit and faith in the truth."
Beyond this, we are chosen to be "in Christ," Himself the Elect One, and as such to have fellowship with one another. At the mount of transfiguration, Peter, James and John are exhorted by the Father (Luke 9:35), "And a voice came out of the cloud, saying, 'This is my Son, my Chosen One; listen to him!'" Even the crowds at Jesus crucifixion recognized that the Christ was chosen of God, even if they did not understand Jesus was that chosen one. Luke 23:35 "And the people stood by, watching, but the rulers scoffed at him, saying, 'He saved others; let him save himself, if he is the Christ of God, his Chosen One!'" That we are in Christ is revealed repeated by Paul, especially in Ephesians, but the clearest statement comes from Colossians 1:27 "To them God chose to make known how great among the Gentiles are the riches of the glory of this mystery, which is Christ in you, the hope of glory."
Because we are in Christ, we are not elected merely as individuals, but we are elected into the community of faith. 1 Peter 5:13 "She who is at Babylon, who is likewise chosen, sends you greetings, and so does Mark, my son." 2 John 13 "The children of your elect sister greet you." And at the end of the age, we will be with Christ and all of the elect (Revelation 17:14): "They will make war on the Lamb, and the Lamb will conquer them, for he is Lord of lords and King of kings, and those with him are called and chosen and faithful."
The Bible also clearly indicates that much of the decrees of God are for the elect. Again, Romans 9:23-24 "in order to make known the riches of his glory for vessels of mercy, which he has prepared beforehand for glory-- even us whom he has called, not from the Jews only but also from the Gentiles." Also, Jesus, in discourse on the Mount of Olives, states (Matthew 24:22) "'And if those days had not been cut short, no human being would be saved. But for the sake of the elect those days will be cut short.'" Whenever these events have, or will, transpire, it is apparent that limitations are placed based on the presence of the elect. Abraham debates with the Angel of the Lord in an attempt to spare the cities of Sodom and Gomorra based upon the presence of just ten “righteous men” (Genesis 18:22-33).
Ever so briefly, election is necessary because after the fall, man lost the Arbitrium, that faculty which enables him to choose God, the ultimate good, and to serve God. We still have Voluntas, the ability to choose in smaller matters, but the ultimate choice has been removed. John 3:3, 5 show this, as does John 3:19-20:
42 Jesus said to them,