God is both merciful and just. Those of His children who choose to believe in Him, live following His precepts (even those of His Church) will still fall into sin. That is our human nature. If we ask for repentance for our failings, God, in His mercy will forgive. Christ tells St. Peter in the Gospel of St. Matthew 17:21 that we are to forgive our neighbor who sins against us "Seventy times seven". God will grant forgiveness only if we ask.

In the parable of the Prodigal Son, did not not father welcome back his son who had fallen away and came home asking forgiveness?

As the Good Shepherd, Christ will not abandon us, but seeks every opportunity to bring us back. Which brings us to God's Justice. Those souls who remain entrenched in their sins, never seeking forgiveness, turning away from opportunities of grace, show the justice of God in that their reward is not eternal bliss, but rather eternal damnation.

As St. Augustine said, and is often quoted: "God created us without us, but He will not save us without us".

ADMG