Are we called because we are special or more worthy than others? No! In fact the opposite is true.
God has called the weak and foolish to confound the wise, “For ye see your calling, brethren, how that not many wise men after the flesh, not many mighty, not many noble, are called: But God hath chosen the foolish things of the world to confound the wise; and God hath chosen the weak things of the world to confound the things which are mighty; And base things of the world, and things which are despised, hath God chosen, yea, and things which are not, to bring to nought things that are: That no flesh should glory in his presence.” (1 Corinthians 1:26-29).
The rest of the world will eventually be called. But it will happen in a pre-arranged order, “For as in Adam all die, even so in Christ shall all be made alive. But every man in his own order: Christ the firstfruits; afterward they that are Christ’s at his coming.” (I Corinthians 15:22-23). Those who are called now will be raised to eternal life when Christ returns, “…and they lived and reigned with Christ a thousand years. But the rest of the dead lived not again until the thousand years were finished. This is the first resurrection.” (Revelation 20:4-5).
Then the rest of the dead will be raised back to a physical existence during which time the words that Christ had recorded in the books of the Bible will be revealed to them. And they will be given the faith, or ability to believe, and the chance to repent and be baptised so they too can be written into the book of life, “And I saw the dead, small and great, stand before God; and the books were opened: and another book was opened, which is the book of life: and the dead were judged out of those things which were written in the books, according to their works… … And whosoever was not found written in the book of life was cast into the lake of fire.” (Revelation 20:12, 15).
When the wise and sceptics of this world who consider the Word of God to be foolishness, are awakened from death and see that the weak and foolish have been glorified they will be absolutely astounded. That is when they will be ready to receive their calling.
To be written into the book of life means that they will be given eternal life. Those who refuse this offer will be destroyed forever in the Lake of fire. Our God is a just God and everyone will be given the opportunity to be reconciled with God and given eternal life.