When you accept Christ as Saviour, you receive the gift of eternal, or everlasting, life.

Romans 6:23For the wages of sin is death; but the gift of God is eternal life through Jesus Christ our Lord.
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For the wages of sin is death; but the gift of God is eternal life through Jesus Christ our Lord.

John 3:15-16 [15] That whosoever believeth in him should not perish, but have eternal life. [16] For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life.
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That whosoever believeth in him should not perish, but have eternal life. For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life.

Please notice that Romans 6:23For the wages of sin is death; but the gift of God is eternal life through Jesus Christ our Lord.
See All... and John 3:15That whosoever believeth in him should not perish, but have eternal life.
See All... speak of “eternal life,” while John 3:16For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life.
See All... speaks of “everlasting life.” When you are saved , you receive both. And while “everlasting” and “eternal” both mean without end, there is a difference in emphasis. “Everlasting” is a term of quantity and emphasizes length of life: everlasting as opposed to temporary. “Eternal,” on the other hand, is a term of quality and emphasizes the kind of life you receive at salvation: eternal as opposed to temporal or earthly. As Christ taught, He came that you might “have life” and that you might “have it more abundantly” (John 10:10The thief cometh not, but for to steal, and to kill, and to destroy: I am come that they might have life, and that they might have it more abundantly.
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Probably the greatest thing about eternal life is that it is given as a present possession.

John 5:24Verily, verily, I say unto you, He that heareth my word, and believeth on him that sent me, hath everlasting life, and shall not come into condemnation; but is passed from death unto life.
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Verily, verily, I say unto you, He that heareth my word, and believeth on him that sent me, hath everlasting life, and shall not come into condemnation; but is passed from death unto life.

When you hear the word and believe on Christ, you have (present tense) everlasting life. Nothing is ever said in scripture about receiving this life in the future. You have everlasting life as a present possession from the point of salvation.

This means that you cannot lose everlasting life. Think about this: if your life has ending today (you are going to perish), then it could not have been without ending (everlasting) yesterday. To lose everlasting life would be an impossibility. Therefore, since to lose everlasting life would be a contradiction of terms, there is only one way to lose your salvation. You must change the meaning of the word “everlasting.” That is the completion of step seven.