A Catholic is supposed to resolve not to sin again and also to express his/her resolution at the time of confession in order to seek absolution from sins already committed by him/her. I wish to know if there is anything in the scriptures which makes the resolution a pre-requirement for seeking absolution from sins .
As explained here, three things are part of the matter of the Sacrament (the 'stuff,' or that which is involved and necessary—such as water, in baptism):
Confession (of sins)
Contrition (sorrow for sin)
Satisfaction (making reparation to God by doing the opposite of indulging in sin, which is to do penance)
Purpose of amendment (intention not to commit the same sin as best you can, honestly, truthfully), however, is related intrinsically to contrition. Because you are not sorry if you both say you are sorry and intend, but don't outwardly make it known, that you in fact plan to do the same in the future!
That is, to make a confession without purpose of amendment (resolution not to sin) is to make an invalid confession, and you cannot recieve the grace given in the Sacrament of Confession.
Refusing to or not having the intention to amend your life and not fall into the same sin with all your strength, is actually the sin of presumption ('God will definitely forgive me if I sin again,' i.e. 'God owes me forgiveness').
And you cannot replace part of the matter for the Sacrament with a sin!
This passage from Sirach (or, Ecclesiasticus) deals with this:
Set not thy heart upon unjust possessions,1 and say not: I have enough to live on: for it shall be of no service in the time of vengeance and darkness. Follow not in thy strength the desires of thy heart: And say not: How mighty am I? and who shall bring me under for my deeds? for God will surely take revenge. Say not: I have sinned, and what harm hath befallen me? for the most High is a patient rewarder. Be not without fear about sin forgiven, and add not sin upon sin: And say not: The mercy of the Lord is great, he will have mercy on the multitude of my sins. For mercy and wrath quickly come from him, and his wrath looketh upon sinners. Delay not to be converted to the Lord, and defer it not from day to day. For his wrath shall come on a sudden, and in the time of vengeance he will destroy thee. Be not anxious for goods unjustly gotten:1 for they shall not profit thee in the day of calamity and revenge.
1 or in the case of habit of sin, illicit pleasures, to which you have no right: the pleasure which comes with sinning
cf. Mt 24:42-51; Luke 12:46; Revelation 22:12.
Similarly, it is gravely disrespectful to abuse the Sacrament of Confession:
How much more, do you think he deserveth worse punishments, who hath trodden under foot the Son of God, and hath esteemed the blood of the testament unclean, by which he was sanctified, and hath offered an affront to the Spirit of grace?
See also 2 Peter 2:20-22, as noted by the commenter below.
First and foremost, it is Christ who makes us worthy to stand before Him and forgives us our sins. If our desire to not sin against the Lord is sincere then He will forgive us and we will experience a peace regarding that matter. Your statement itself is sort of contradictory. Because even if a priest formally forgives you(as per the definition of absolution), only you and God and the devil knows if you still have sin in your heart. Say for instance you told the priest that you have resolved not to sin (while in fact you didn't) and you received absolution also but does really matter before God? Because it is God who justifies and forgives and before Him you are still a sinner...