When we turn to God in repentance through faith in Christ Jesus as Lord and Savior, God at that time takes all of our sin debt (past, present and future) and stamps it paid in full (by Christ Jesus when sin was judged on the cross of Calvary). (2 Corinthians 5:21; Romans 8:1)

From that time forward, God chooses to remember our sin no more as to our salvation. All of the guilt and penalty of sin is removed once and for all. (Hebrews 10:17; Romans 8:1) We are also restored to God’s favor and adopted into His family. We become joint heirs with Christ Jesus of all that God has to offer. (Romans 5:1; Galatians 4:4-7)

The Bible says this:

"And you also were included in Christ when you heard the word of truth, the gospel of your salvation. Having believed, you were marked in Him with a seal, the promised Holy Spirit, who is a deposit guaranteeing our inheritance until the redemption of those who are God's possession--to the praise of His glory." (Ephesians 1:13-14)

We (God's children) have an inheritance, kept for us in heaven, that can never perish, spoil, or fade. (1 Peter 1:3-5) Look what Jesus said:

"My sheep (God's children) listen to My voice; I know them, and they follow Me. I give them eternal life, and they shall never perish; no one can snatch them out of my hand. My Father, who has given them to Me, is greater than all; no one can snatch them out of My Father's hand." (John 10:27-29, words in parenthesis are mine)

God will never leave, nor forsake, His children. (Hebrews 13:5)