How can one maintain the feeling of asceticism in this world and drawing closer to Allah, with which Allah has blessed him after repentance?

To maintain your uprightness, cultivate asceticism (zuhd) regarding this world, and turn towards the Hereafter, you must hold yourself accountable, remember your shortcomings, and beware of conceit, all while keeping in mind your deficiencies towards your Lord. Remember Paradise and its delights, and Hellfire and its torments, so that they may serve as an impetus for you to strive in worship and asceticism. Reflect on the insignificance of this world, and that it is worth nothing in the sight of Allah. Ponder Allah's Names and Attributes so that their lights may illuminate your heart. Strive in acts of worship to attain peace of heart and its bliss. Nevertheless, beware of Satan and his cunning, and always supplicate to Allah, so that He may perpetuate the sweetness of closeness to Him in your heart.