Does God Forgive Serious Sins?

MERCY is one of God's formost qualities.
{Psalm 86:15}

How extensive is his mercy?
A Psalmist wrote: " If error's were what you watch, O Jah,
O Jehovah, who could stand?
For there is the true forgiveness with you, in order that you may be feared."
{Psalm 130:3,4}

Another Passage reads:" As far off as the sunrise is from the sunset, so far off from us he has put our transgressions.
As a father shows mercy to his sons, Jehovah has shown mercy to thoses fearing him.
For he himself well knows the formation of us, remembering that we are dust."
{Psalm 103:12-14}