Be Saints

Padre Pio is quoted as saying: "The Spirit of God is a spirit of peace. Even in the most serious faults He makes us feel a sorrow that is tranquil, humble, and confident. This is precisely because of His mercy. The spirit of the devil, instead, excites, exasperates, and makes us feel, in that very sorrow, anger against ourselves. We should, on the contrary, be charitable with ourselves first and foremost. Therefore if any thought agitates you, this agitation never comes from God, who gives you peace, being the Spirit of Peace, but from the devil."
The temptation to dwell on our sins may not even seem wrong, but Padre Pio reminds us otherwise. It is easy to look over our sins and be dismayed, thinking "I am too terrible and evil for even God to love me! How could He forgive me for such things? I could never become a saint and attain Heaven!" However, if we have confessed these sins and been absolved by a priest, we must believe that Jesus has truly forgiven us and wiped these offences from His mind. With God being the Spirit of Peace, we should be at peace having acessed His mercy, rather than angry with ourselves.
Despite our sinful nature, God forgives a contrite heart. Despite our lowliness, God has opened the Heavens to us, and we know that He has given us the means to get there. If Satan successfully uses this tactic of having us dwell on our sins, we will not trust in the inexhaustible mercy of Jesus, nor believe that we are capable of gaining the Eternal Home we were created for. Yes, as humans we are weak and evil, ungrateful and uworthy, but when we allow these thoughts to overcome us with dispair, we allow the Enemy entrance into our minds.
What can we do, then, when these thoughts enter into our minds? Well, firstly we can thank our Lord and praise Him for loving and dying for us anyways. Secondly, instead of banishing the reminder of our sins, this reminder can be put to good use when we suffer. As Catholics we know that before entering Heaven we must atone for our sins either in this life or in Purgatory. Any of our trials and pains can be offered up for our own sins and those of the world. In keeping with St. Therese's Little Way, even the smallest things- such as patiently enduring a headache instead of taking pain medication- can be offered for our sins.
If you have little inclination to be patient during trials, I find it very helpful to (of course) remember our Lord's Passion and what He was willing to suffer for sinners. I also find it very helpful to call to mind my own sins. Instead of letting them bring me down and lose hope for an eternity in Heaven, I remind myself the pain these failings have brought to Jesus' Sacred Heart and that someday these will need to be repaid by my own suffering. Usually it then makes me laugh to think I could complain about such a small trial, especially when I know that I deserve it and so many more. I am extremely far from enduring any pains and suffering as well as I should, but reminding myself what I must pay before entering into Heaven definitely makes me more inclined to be patient and prayerful instead of complaining.
When we call our sins to mind as we suffer, I suppose this all boils down to one important question: "Do I want to atone for this now... Or later?" Now is probably ideal.