​After entering into a relationship the believer needs to remain faithful until the end to enter into eternal life.

But he that shall endure unto the end, the same shall be saved. Mat 24.13

“For we are made partakers of Christ, If we hold the beginning of our confidence steadfast unto the end.” Hebrews 3:14 .

If a saved man choose to be  unfaithful his name will be blotted out from book of life

Revelation 3:5 , “He that overcometh . . . I will not blot out his name out of the book of life.”

“If any man draw back, my soul shall have no pleasure in him.” Hebrews 10:38
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“If we sin willfully . . . there remaineth no more sacrifice for sins.” Hebrews 10:26

What can we do to remain in this saving relationship

“If ye do these things, ye shall never fall.” 2 Peter 1:10

“If thou continue in his goodness: otherwise thou also shalt be cut off.” Romans 11:22