Throughout Scripture, there are many analogies between things in the natural realm and corresponding things in the spiritual realm. God uses these to help us human beings, who do understand the natural realm, understand spiritual truth also. One such example is the idea of being “born again.”
Think about a normal human birth — you know, “Wa-a-a-h!” There you were, a screaming bundle of life. Why were you screaming? Because you were peeved about having to wait until later in life to get a liver? No. You “came from the factory” completely, completely complete, with everything you needed for growth perfectly packaged within you.
Why then would your spiritual birth leave you lacking something necessary for you to grow to spiritual maturity, something you must acquire later on in your spiritual life? It doesn’t. We will see from Scripture that at the moment you are born again, that is, born of God, you received from your heavenly Father the gift of holy spirit—all you will ever need, the fullness of God in Christ in you, God’s divine nature.
The first time you were born was because of a seed—one that your father gave your mother. Because of Adam’s sin, it was a “corruptible” seed, that is, the life it generated will not last forever—it will eventually die. But when one is born again, he is born of incorruptible seed.
1 Peter 1:23
For you have been born again, not of perishable seed, but of imperishable, through the living and enduring word of God. 
The imperishable seed is the very life of God planted within you in the gift of holy spirit. As a Christian, you are now endued with a new, divine nature, and you have the potential to be like your Father.
2 Peter 1:2-4 (KJV)
(2) Grace and peace be multiplied unto you through the knowledge of God, and of Jesus our Lord,
(3) According as His divine power hath given unto us all things that pertain unto life and godliness, through the knowledge of Him that hath called us to glory and virtue;
(4) Whereby are given unto us exceeding great and precious promises; that by these ye might be partakers of the divine nature, having escaped the corruption that is in the world through lust.
In 1 Peter 1:23, we see that one’s new, spiritual birth comes via hearing and believing the Word of God. 2 Peter 1:2 and 3 speak of the “knowledge of God and of Jesus our Lord” as the means by which we learn how to become partakers of the divine nature. It is in God’s Word that one finds the knowledge of how to get born again. Where is this in the Word?
(8) But what does it say? “The word is near you; it is in your mouth and in your heart, that is, the word of faith we are proclaiming:
(9) That if you confess with your mouth, “Jesus is Lord,” and believe in your heart that God raised him from the dead, you will be saved.
(10) For it is with your heart that you believe and are justified, and it is with your mouth that you confess and are saved.
The “word of faith” is that Word of God one must believe in his heart if he wants to be saved. Saved from what? Death. What saves you from death? Life. How do you get life? Birth. Thus we see that to be “saved” is the same as to be born again. Simple, huh? Let’s allow another section of Scripture to clarify just what it means to be “saved.” Note the “liquid” terminology.
Titus 3:5 and 6 (Amplified Bible)
(5) He saved us, not because of any works of righteousness that we had done, but because of His own pity and mercy, by [the] cleansing (bath) of the new birth (regeneration) and renewing of the holy spirit [no article “the,” read “of holy spirit”].
(6) Which He poured out [so] richly upon us through Jesus Christ our Savior.
In these verses, we can clearly see that to be “saved” (from death) is to be born again and simultaneously receive new life in the gift of holy spirit. In the words “cleansing bath” and “poured out,” we see the liquid analogy—the reason why we call God’s divine deposit within us a “liquid asset.” The word “richly” indicates that God did not hold back anything when He gave us the gift of holy spirit.
Three great statements of the Lord Jesus Christ’s goodness follow the formula for salvation in Romans 10:9 and 10.
(11) As the Scripture says, “Anyone who trusts in him will never be put to shame.
(12) For there is no difference between Jew and Gentile— the same Lord is Lord of all and richly blesses all who call on him,
(13) for, Everyone who calls on the name of the Lord will be saved.”
If you needed financial help, would you ask a poor man or a rich man? A poor man might desire to help you, but he would lack the means. A rich man has the means to help, if he wills to do so. The Lord Jesus became poor by giving his life for us, and God raised him from the dead to the riches of a limitless inheritance (Heb. 1:4). That is why he is rich unto all who call on him. He gives a gift to each one. This gift is the holy spirit that Jesus received from God, and gives to each person who believes in him as Lord. The first time that the exalted Lord Jesus did this was on the Day of Pentecost (Acts 2:33). This gift of holy spirit is the “earnest” (Eph. 1:14—KJV), or guarantee, that your “earthen vessel” will, at his appearing, be replaced by a perfect body like the Lord’s.
 This verse is a wonderful example of the figure of speech Ellipsis, which is when a word that would ordinarily be in the text is left out to emphasize another word. In this verse, “imperishable” is an adjective and needs a noun to modify. We would expect the verse to read “born again, not of perishable seed, but of imperishable seed.” By leaving out the second “seed,” God emphasizes the imperishability of the seed. For more on Ellipsis, see E.W. Bullinger’s Figures Of Speech Used in the Bible.