Meaning and definition of holiness in the bible. Why is necessary and important?

Holiness is first of all righteousness. Holiness is a path that begins with conversion, the passage from a life full of sins to a life of righteousness. A clear example of righteousness is the good samaritan:
"A man was going down from Jerusalem to Jericho, when he was attacked by robbers. They stripped of his clothes, beat him and went away, leaving him half dead. A priest happened to be going down the same road, and when he saw the man, he passed by the other side. So too, a levite, when he came to the place and saw him, passed by the other side. But a samarithan, as he traveled, came where the man was; and when he saw him, he took pity on him. He went to him and bandage him wounds, pouring on oil and wine. Then he put the man on his own donkey, brought him to an inn and took care of him. The next day he took out two denarii and gave them into the innkeeper. "Look after him" he said, "and when I return, I will reimburse you for any extra expense you may have"
Which of these three do you think was a neighbor to the man who fell into the hands of the robbers?" Luke 10:25-37
Conversion implies that sin is no longer a habit but the exception, conversion is an easter, an inner step.
Holiness is a gift, a transmissible perfection of God, this is how it is explained in the first epistle to Saint Peter:

But the holiness is more than a life of righteousness, is a life of fear of the lord, that is, constancy, firmness, devotion, ecuanimity, stability. Holiness is a glody righteousness. Righteousness and fear of god are necessary gifts and go together.
This is how we receive the holy spirit, the gnosis. Once the holy spirit is received there is a further step: the perseverance, the trust in god, and the eternal life.
Holiness as such is the fruition of the gifts of the holy spirit in our lives: "love, joy, peace, forbearance, kindness, goodness,faithfulness, gentleness, self-control", Galatians 5:22-23
The fruits of the holy spirit arise as a result of the contemplative activity, the eternal life:" this is the eternal life, that they know you, the only true god." John 17:3
In a practical sense, holiness has to do with the formation of the character. The fruits of the spirit are the description of the character of God.
The holiness is the ultimate goal of the spiritual human life.
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