We should make it a habit to beseech Allah’s forgiveness as much as we can.

We will receive numerous benefits for doing so.

The following are but a few of them:

Forgiveness of sins

Allah quotes Noah speaking to his people:

{Ask forgiveness from your Lord; for He is Oft-Forgiving.} (71:10)

It is a reason for the rains to fall

Noah continues:

{He will send rain to you in abundance.} (71: 11)

Increase in wealth

Noah continues:

{And give you increase in wealth and children.} (71: 12)

Prosperity and success

Noah continues:

{And provide gardens for you and provide rivers for you.} (71: 12)

This expresses the good of this world that Allah provides us. The term “gardens” here refers to worldly provisions as well as the gardens of Paradise in the Hereafter. It also refers to the good that comes as a result of the water Allah provides to the Earth.

Increased strength

This comprehends all kinds of strength. As Prophet Hud said to his people:

{O my people! Ask forgiveness of your Lord, then turn unto Him repentant; He will cause the sky to rain abundance on you and will add unto you strength to your strength.} (11: 52)

This includes the inner strength which comes from having peace of mind and a conscience that is free from the burden of sin.

A good life

Allah says:

{Ask forgiveness of your Lord and turn to Him repentant. He will cause you to enjoy a fair estate until a time appointed.} (11: 3)

Life is good to those who are righteous and God-fearing. It is also good to those who return to Allah in repentance, asking His forgiveness, and compensating for their sins by engaging in good deeds.

Relief from hardships

Allah says:

{Allah will not punish them while they are asking His forgiveness.} (8: 33)

This is because when we seek forgiveness, it dissuades us from persisting in sin. We are realizing and acknowledging our mistakes, not rationalizing them.

Allah’s mercy

Allah says:

{Beseech Allah’s forgiveness, that perchance you will be shown mercy.}(27: 46)

It atones for the mistakes made when we interact with one another

In the latter part of his life, whenever the Prophet stood up from meeting with people, he used to say:

“Glory and praise be to Allah. I bear witness that there is no God but Him. I beseech His forgiveness and turn to Him in repentance.” (Al-Bukhari and Muslim)

The first time he did this, a man asked him:

“You have said something you have never said before.”

The Prophet replied:

“It atones for whatever happened during the meeting.”

It placates our fears and worries

The Prophet said:

“Whoever asks Allah’s forgiveness often, Allah will give them relief from every worry, make a way out for them from every difficulty, and provide for them from whence they least expect it.” (Abu Dawud)

Ibn al-Qayyim comments in Zad al-Ma`ad:

As for the effect that beseeching Allah’s forgiveness has on our fears, worries, and difficulties, one thing all rational people from all nations and faith traditions agree upon is that sins and corruption cause anxiety, fear, and depression, as well as diseases of the heart.

Indeed, even after the sinful people have had their fill from indulging in sin, the resultant anxiety and worry that remains in their hearts causes them to return to the sin again to ward away those feelings. One of the most notorious sinners penned these verses:

A draught I drank for the pure pleasure that it gave

The next to cure what the first draught had made me crave!

Since this is the effect that sins and transgressions have on the heart, the only real cure is to beseech Allah’s forgiveness.

It seems that Ibn al-Qayyim is alluding to addiction, which not only relates to alcohol and drug use, but to any habitual sin, like illicit affairs and pornography. This requires appealing to Allah for forgiveness frequently, as well as seeking treatment, engaging in wholesome activities, and keeping good company. Addiction of any kind requires professional help, since addiction itself compels the perpetration of the act, even in the absence of any pleasure.

The pleasure of the activity might have been what got the addict started in the first place, but then when it turns into a psychological or physical dependency, the compulsion to do it remains even in the absence of any positive sensation.

The following advice is attributed to Luqman: “My son, make it your tongue’s habit to say: ‘O Allah, forgive me,’ since there are times during the day that no petitioner is turned down.” (Shu`ab al-Iman (1120))

Aisha said: “Blessed are those who have in their record of deeds that they sought Allah’s forgiveness often.”

Abu al-Minhal said:

“The best neighbor one can have in the grave is the forgiveness that one had sought from Allah.”

Qatadah said: “This Quran reveals to you your affliction and its cure. Your sins are your affliction and the cure is to ask Allah’s forgiveness.”

Al-Hasan said: “Ask Allah’s forgiveness frequently, when you are at home, when you are dining, when you are on the road, when you are shopping, and at your gatherings. You never know when Allah will bestow His forgiveness.”

O Allah! We have wronged ourselves greatly, and no one forgives sins but You, so forgive us and have mercy on us. Indeed You are the Oft-Forgiving, Most Merciful.

http://www.onislam.net/english/reading-islam/living-islam/growing-in-faith/491671-10-benefits-of-asking-gods-forgiveness.html