I wonder what answer you have come up with, perhaps some of them run along these lines:
To have a clearer conscience
To please God
To please your family and peers
It is what is expected of you
To gain your salvation
Your answers may not be listed in the above but I’ll suggest a few reasons for why we should pursue holiness:
1. Because God is holy* - We should pursue holiness because God is holy and because we want to be like him. If your hearts desire is to be truly like God, to be like His Son Jesus Christ, then pursuing holiness becomes something of a joy rather than a chore. It becomes a delight to the soul. Consider who your heroes are and the excellent things that they do, is it not your joy to be able to imitate them and to be like them. Therefore you speak consistently of wishing to be like them and it excites your heart. Your motivation is born of excitements and the joy in being like them captivates your soul because there is something about them that you truly love and wishes was your own. Likewise consider God in a greater way, let him first excite and captivate your soul, let his holiness be like a pearl, a treasure that you desire to obtain, let his whole being be the end of your heart and you shall pursue his holiness in a joyful and easy way because your heart truly loves him and really wants to be like him. Until you have this joy of becoming like him in your heart, your pursuit will be like that of a boy who does an unwilling errand for his mother.
2. Because you want to see him* - The writer to the Hebrews tells us that without holiness no one will see God. If you truly want to see God because you truly love him, then your heart should be consumed with the passion of being holy. A man would travel a million miles to see the woman he loves so dear. He would gladly endure the storm, farewell the pleasures, and surrender his possessions, if at the end of it all he could be with the woman he loves forever. Likewise, are you willing to forego your passions and pleasures in order to be conformed to the image of Christ so that at the end of it all, you see God and dwell with him forever. You really need first to have a heart that is serious about wanting to see God, otherwise there will be no pleasure in your pursuit of holiness and your pursuit will only resemble that of a boy who really doesn’t want to go back home for Christmas but has to and it frustrates him
3. Because you love God’s grace on your life *- God has done a wonderful thing for mankind in that in his mercy and grace He sent forth his dear Son to die for our sins. And those who accept his mercy and forgiveness are giving a new life and reconciled back to God. They are now to live a godly and holy life as a result of being thankful for what God has done for them. Because they are thankful for God’s grace, they seek to throw away every thing that brought about the death of God’s Son in the first place. As a result of this grace and mercy shown to them, they pursue holiness with a joyful and thankful heart. They are like a boy who gladly goes to the grocery shop for their mother because they appreciate all of the sacrifices that their mother has made for them.
Whatever answers you may have come with in chasing after holiness, I pray that you first settle in your heart that your pursuit is because God is holy and you really want to be like him, that you really want to see him and because you love his grace upon your life.*
Of course we are holy in Jesus Christ and counted righteous in him by his righteousness nevertheless we are to conform to this in this life and to reflect more of his image. We have the Holy Spirit to help us and God himself has not abandoned us to this task alone but He his determined to complete the good work that He started in you.
* 1Peter 1:16
* Hebrews 12:14
* Titus 2:11-14
* There are more good and valid reasons to seek after God’s holiness which leads to a joyful and glad pursuit. And I believe a right motivation determines whether we seek it with pleasure or do it because we have to and therefore not have a great in God’s holiness.