Two factors are involved in man's salvation: the grace of God and the will of man. Both must work together, if salvation is to be attained. Repentance is a Mysterion through which he who repents for his sins confesses before a Spiritual Father who has been appointed by the Church and has received the authority to forgive sins, and receives from this Spiritual Father the remission of his sins and is reconciled with the Deity, against Whom he sinned. Repentance signifies regret, change of mind. The distinguishing marks of repentance are contrition, tears, aversion towards sin, and love of the good.
Repentance is the renewal of baptism. Repentance is a contract with God for a second life. A penitent is a buyer of humility. Repentance is constant distrust of bodily comfort. Repentance is self-condemning reflection, and carefree self-care. Repentance is the daughter of hope and the renunciation of despair.
A man who falls into sin is different from the way he was created. He is different, because he changes by his own actions the way he was meant to be. Man renounces himself when he becomes a different person through repentance. He leaves a corrupted man, which he had become through sin, and becomes such as he once was created, through mercy.
One day, a young monk came to see an elder and asked him, 'What must I do, Father? I fall continuously in the same sin.' The elder replied, 'If you fall into sin, get up and do penance.' Monk: 'And if I fall again?' Elder: 'Then get up and repent of your sin again.' Monk: 'But until when?' Elder: 'Until your death.'
True repentance consists of withdrawing from sin and nurturing hatred for it. For, lo, when someone says from his heart: I have hated deceit and been repelled by it - then God accepts him with joy.
If the main goal of the repentant sinner should be total, light-bearing and blessed communion with God, then the main hindrance to this is the existence of the passions still active and working in him - the virtues being as yet unsealed in him - and the unrighteousness of his powers. Therefore his main work upon conversion and repentance should be the uprooting of the passions and sealing the virtues - in a word, correcting himself.
If Christ is in you through the frequent communion of the Holy Sacrament, then be yourself wholly like unto Christ: meek, humble, long-suffering, full of love, without attachment to earthly things, meditating upon heavenly ones, obedient, reasonable. Have His spirit unfailingly within you.
You will not perish on account of thoughts with which you do not sympathize and from which you at least try to be freed. Only repent, & humble yourself. And God will forgive you.