Asalamualaikum wrt wb,
Here are two articles that you may find beneficial. The first explains the difference between the heart and the soul and how to overcome the whispers of the nafs and the shaitan, and the second mentions some of the rewards of striving to purify our nufoos.
Jihâd an-Nafs (Striving against the Soul)
Taken from the 'Ihyâ ‘Ulûm ad-Dîn' (The Revival of the Religious Sciences)
a) Meaning of nafs: It has two meanings. First, it means the powers of anger and lust in a human being... and this is the usage mostly found among the [so-called] people of tasawwuf, who take "nafs" as the comprehensive word for all the evil attributes of a person. That is why they say: one must certainly do battle with the soul/self and break it (la budda min mujahadat al-nafs wa kasriha), as is referred to in the hadîth: A`da `aduwwuka nafsuka al-lati bayna janibayk (Your worst enemy is your nafs which lies between your flanks) Al-‘Irâqî says it is in Bayhaqî on the authority of Ibn ‘Abbâs and its chain of transmission contains Muhammad ibn Abd al-Rahman ibn Ghazwan, one of the forgers.
The second meaning of nafs is the spirit, the human being in reality, his self and his person. However, it is described differently according to its different states. If it assumes calmness under command and has removed from itself the disturbance caused by the onslaught of passion, it is called "the satisfied soul" (al-nafs al-mutma'inna)... In its first meaning the nafs does not envisage its return to God because it has kept itself far from Him: such a nafs is from the party of shaytân. However, when it does not achieve calmness, yet sets itself against the love of passions and objects to it, it is called "the self-accusing soul" (al-nafs al-lawwama), because it rebukes its owner for his neglect in the worship of his master... If it gives up all protest and surrenders itself in total obedience to the call of passions and shaytân, it is named "the soul that enjoins evil" (al-nafs al-ammara bi al-su’)... which could be taken to refer to the soul/self in its first meaning.
b) God has armed soldiers which He has placed in the hearts and the souls and others of His worlds, and none knows their true nature and actual number except He... [He proceeds to explain that the limbs of the body, the five senses, will, instinct, and the emotive and intellective powers are among those soldiers.] Know that the two soldiers of anger and sexual passion can be guided by the heart completely... or on the other hand disobey and rebel against it completely, until they enslave it. Therein lies the death of the heart and the termination of its journey towards eternal happiness. The heart has other soldiers: knowledge (‘ilm), wisdom (hikma) and reflection (tafakkur) whose help it seeks by right, for they are the Party of God against the other two who belong to the party of shaytân...
God says: "Have you seen the one who takes as his god his own desire?" (25:43) And "He followed his own desire. So his example is like that of a dog: if you chase him he pants, or if you leave him, he [still] pants." (7:176) And about the person who controlled the passion of his soul/self God says: "But as for he who feared the standing before his Lord and restrained the soul from [his] desire, then indeed, Paradise will be his refuge." (79:40-41).
Know that the body is like a town and the intellect of the mature human being is like a king ruling that town. All the forces of the external and internal senses he can muster are like his soldiers and his aides. The soul/self that enjoins evil (nafs ammara), that is, lust and anger, is like an enemy that challenges him in his kingdom and strives to slaughter his people. The body thus becomes like a garrison-town or sea-outpost, and the soul like its custodian posted in it. If he fights against his enemies and defeats them and compels them to do what he likes, he will be praised when he returns to God’s presence, as God said: "[who strive and fight] in the way of God with their wealth and their lives over those of remained [behind], by degrees. And to all God has promised the best [reward]." (4:95).
c) The thoughts that stir one’s desire are of two kinds... praiseworthy, and that is called "intuition" (ilhâm), and blameworthy, and that is called "whispering" (waswasa)... The heart is owned mutually by a shaytân and an angel... The angel stands for a creature which God has created for the overflowing of benefit, the bestowal of knowledge, the unveiling of truth, the promise of reward, and the ordering of the good... The shaytân stands for a creature whose business is to be against all this... Waswasa against ilhâm, shaytân against angel, success (tawfîq) against disappointment (khidhlan).
The Prophet sallallaahu 'alayhi wa sallam said: "There are two impulses in the soul, one from an angel which calls towards good and confirms truth; whoever finds this let him know it is from God and praise Him. Another impulse comes from the enemy which leads to doubt and denies truth and forbids good; whoever finds this, let him seek refuge in God from the accursed devil." Then he recited the verse: "Satan threatens you with poverty and orders you to fahshâh (immorality)" (2:268) [Tirmidhî: hasan; Nisâ'î; ‘Irâqî did not weaken it].
Hasan al-Basrî said: "Two thoughts roam over the soul, one from God, one from the enemy. God shows mercy on a servant who settles at the thought that comes from Him. He embraces the thought that comes from God, while he fights against the one from his enemy. To illustrate the heart’s mutual attraction between these two powers the Prophet sallallaahu 'alayhi wa sallam said: "The heart of a believer lies between two fingers of the Merciful" [Muslim, Ahmad, Tirmidhî, Ibn Mâjah]... The fingers stand for upheaval and hesitation in the heart... If man follows the dictates of anger and lust, the dominion of shaytân appears in him through idle desires (hawâ) and his heart becomes the nesting-place and container of shaytân, who feeds on hawâ. If he does battle with his desires and does not let them dominate his nafs, imitating in this the character of the angels, at that time his heart becomes the resting-place of angels and they alight upon it...
The Prophet sallallaahu 'alayhi wa sallam said: "There is none among you in whom there is not a devil" They said: "Even in you, O Messenger of God?!" He said: "Even in me, but God helped me to overcome him and he has submitted to me, so he doesn't order anything except good" [Muslim]... The mutual repelling of the soldiers of the angels and the devils is constant in the battle over the heart, until the heart is conquered by one of the two sides which sets up its nation and settles there... And most hearts have been seized by the soldiers of shaytân, who fill them with the whispers that call one to love this passing world and disregard the next.
d) The Prophet sallallaahu 'alayhi wa sallam said: al-mujahidu man jahada nafsahu fi ta`at Allah `azza wa jall ("The struggler is the one who strives against his soul/self in obedience to God, the Mighty and Majestic") [Tirmidhî, Ibn Mâjah, Ibn Hibbân, Tabarânî, Hâkim, etc.]... Sufyân al-Thawrî said: "I never dealt with anything stronger against me than my own soul/self; it was one time with me, and one time against me"... Yahyâ ibn Mu`âdh al-Râzî said: "Fight against your soul/self with the four swords of training: eat little, sleep little, speak little, and be patient when people harm you... Then the soul/self will walk the paths of obedience, like a fleeing horseman in the field of battle."
The Heaven of this World
From al-Wâbil as-Sayyib min al-Kalim at-Tayyib
Translated by Micheal Abdur-Rahmân Fitzgerald and Moulay Youssef Slitine
I heard the Shaykh of Islâm, Ibn Taymiyyah - may Allâh sanctify his soul - say, 'Truly, there is a Heaven in this world, [and] whoever does not enter it, will not enter the Heaven of the next world.' And once he said to me, 'What can my enemies do to me? I have in my breast both my Heaven and my garden. If I travel they are with me, and they never leave me. Imprisonment for me is a religious retreat [khalwa]. To be slain for me is martyrdom [shahâda] and to be exiled from my land is a spiritual journey [siyaha].'
During his imprisonment in the fortress, he would say, 'I could not be more grateful for this blessing were I to have this entire fortress in gold'; or, 'I could never repay them for the good that has come to me in [this prison].' [Ibn al-Qayyim accompanied Ibn Taymiyyah to prison (cf. Introduction).] And in prostration he would say, whilst in a state of imprisonment 'O Allâh, help me in my gratitude to You, remembrance of You and the most comely worship of You' as much as Allâh willed. [A prayer recommended by the Prophet to Mu'adh. Nasâ'î, Sahw, 1286; Abû Dâwûd, Salât, 1301]
Once he said to me, 'The real prisoner is someone whose heart is imprisoned from his Lord; the true captive is someone captured by his passions.' And when he entered the fortress and was inside its walls, he gazed upon them and recited the verse, 'And a wall between them is struck which has a gate. On the inside there is a mercy, on the outside punishment.' [Qur'ân LVII:13]
Allâh knows, I have never seen anyone who had a better life than his. Despite the difficulties and all that expunges comfort and luxury, nay, things completely opposite to them; despite intimidation and oppression, Ibn Taymiyyah had a purer life than anyone could. He was the most generous, the strongest of heart and the most joyful of soul, with 'the radiance of bliss' on his face. ['Nadratun al-na'im'. Qur'ân LXXXIII:24]
When we were seized with fear and our thoughts [about Allâh's decree] turned negative, and the earth grew narrow for us, we would go to him. No sooner did we look at him and hear his words than all these [feelings] would leave us, to be replaced by relief, strength, certainty and tranquillity. So glory be to the One who lets His servants witness His Heaven well before they meet Him, who opens its doors to them in this world of deeds and who gives them something of its refreshment, its breeze and its perfume - that they might seek it and hasten towards it with all their strength.
A gnostic once said, 'If kings and the sons of kings knew what we had , they would try to take it from us by the sword!' Another said: 'How pitiful, the worldly people! They leave this life without ever having tasted the sweetest thing in it.' When asked what that was, he replied, 'The love of Allâh, the knowledge of Allâh and the remembrance of Allâh,' or words to that effect. [Possibly referring to the saying by 'Abdullâh ibn al-Mubârak: 'Worldly people leave the world before having feasted on the sweetest thing in it.' They asked him what that was and he answered, 'The knowledge of Almighty Alâh.' Isfahânî, Hilyâ, VIII:167] Another said: 'There are times when the heart dances in joy.' And another said, 'There are times when I say, If the people of Heaven have anything like this, how truly sweet their lives!'
To love Allâh, to know Him intimately, to remember Him constantly, to find peace and rest in Him, to make Him alone the [ultimate] object of love, fear, hope and trust; to base one's act on His control of His servant's cares, aspirations and will - such is the world's Heaven, and such is a blessing with which no other blessing can compare. It is by this that the hearts of those who love Allâh are gladdened and that the gnostics find life. As their hearts are gladdened by Allâh, so others are gladdened by them. For whoever finds his source of gladness in Allâh, gladdens all hearts; whoever does not, finds nothing in this world but restlessness.
Anyone with life in his heart will confirm this. But someone whose heart is dead will only estrange you from Allâh; and so seek intimacy [with Allâh] without him, when you can, for his mere presence will estrange you. If you are tested by him, show him only your outer aspect, but leave him behind in your heart. Depart from him with your soul and do not let him distract you from the one who is most important to you. Know that the greatest of all losses is the involvement with someone who weakens your relationship and standing with Allâh, cutting you off from Him, wasting your time, dispersing your heart, weakening your resolve and dividing your aspirations. Therefore, if you are tested with this [kind of situation] - and it is inevitable that you will be - then bear up for the sake of Allâh, and acknowledge Him as much as you are able.
Draw near to Allâh by whatever of it pleases Him. Make your association [with worldly people] a profit not a loss. Be like the man travelling along, whom another invites to stop: seek to take him along with you. When he comes along, lead him but be not lead by him. And if he refuses, and you have no hope that he will journey, then [at least] do not let him detain you. Rather, hasten on, pay him no heed. Do not [even] turn in his direction, for he is a highway robber regardless.
Protect your heart and be careful of how you spend your day and your night. Let not the sun set on you before you reach camp, 'lest you be carried off'. Nor let the dawn find you abandoned in the camp after the caravan has moved on, and the time is nigh for you to reach them.