"Strive to live in peace with everybody and pursue that consecration and holiness without which no one will [ever] see the Lord." Hebrews 12:14 (Amplified)
Holiness is hard!
Look at the two main verbs in this verse "strive" and "pursue". Those are extra effort type words. They require energy and determination - and desire.
What is holiness and why is it so hard?
Well, the "what it is" is "why it is" so hard.
Holiness is consecrating yourself to God, as the Amplified renders it. Consecrate means that I set myself apart from my selfish desires, my selfish ambitions, my sinful past and give myself completely to God for the purpose of being made holy by Him. You or I cannot make ourselves holy, we can only repent of our sins and renounce sin to give ourselves unreservedly to God so He can make us holy by the cleansing of His blood and the indwelling of His Spirit.
Holiness refers to the condition of your heart in relationship to God. Holy people love God with all their heart and all of their mind. Holiness allows the Holy Spirit to take up residence in your heart empowering you to overcome temptation and sin.
Holiness purifies your motives so that whatever you do is fueled by love (for God and for others). Holiness is being able to fulfill the Great Commandment by loving God and loving others as yourself.
In this verse holiness is equated with peace. You cannot be holy with God while you live in turmoil with others.
So, holiness is difficult because it requires being reconciled on two levels of relationship - holy with God and at peace with men. That doesn't happen automatically. It doesn't happen accidentally. You have to "strive" against your selfish nature and you must "pursue" God's nature.
But holiness is necessary and required of those who desire to see God - Who also happens to be holy.
Holiness really matters! Does it matter to you?