Allah will accept the believers' repentance

And he who repents and does righteousness does indeed turn to Allah with [accepted] repentance. (Surat al-Furqan, 71)

Satan promises you poverty and commands you to avarice. Allah promises you forgiveness and abundance. Allah is All-Encompassing, All-Knowing. (Surat al-Baqara, 268)
[It was so that] Allah may punish the hypocrite men and hypocrite women and the men and women who associate others with Him, and that He may accept repentance from the believing men and women. Allah is Ever-Forgiving, Most Merciful. (Surat al-Ahzab, 73)
Allah has promised those who believe and do right actions forgiveness and an immense reward. (Surat al-Maida, 9)

Allah will replace the believers' wrong actions into good

Except for those who repent and believe and act rightly: Allah will transform the wrong actions of such people into good. Allah is Ever-Forgiving, Most Merciful. (Surat al-Furqan, 70)

But as for those who believe, do right actions, and believe in what has been sent down to Muhammad - and it is the truth from their Lord - He will erase their bad actions and better their condition. (Surah Muhammad, 2)

Those are people whose best deeds will be accepted and whose wrong deeds will be overlooked. They are among the Companions of Paradise, in fulfillment of the true promise made to them. (Surat al-Ahqaf, 16)

Allah will make His religion superior and destroy falsehood

Allah has promised those of you who believe and do right actions that He will make them successors in the land, as He made those before them successors, and will firmly establish for them their religion with which He is pleased and give them, in place of their fear, security. They worship Me, not associating anything with Me. Any who do not believe after that, such people are deviators. (Surat an-Nur, 55)

Allah was pleased with the believers when they pledged allegiance to you [O Muhammad] under the tree. He knew what was in their hearts, sent down serenity to them, and has rewarded them with an imminent victory. (Surat al-Fath, 18)

Say: "Truth has come and falsehood has vanished. Falsehood is always bound to vanish." (Surah Maryam, 81)

Such people [believers] are the inheritors [as successors over the land and of the bounties in the hereafter]. (Surat al-Mu'minun, 10)

Allah supports believers in difficult times with His angels

If you are steadfast and have fear of Allah and they come upon you suddenly, your Lord will reinforce you with five thousand angels, clearly identified. (Surah Al 'Imran, 125)
The angels descend upon those who say: "Our Lord is Allah," and then go straight: "Do not fear and do not grieve, but rejoice in the Garden that you have been promised." (Surat al-Fussilat, 30)

Allah helps those who help His religion

He will guide them, better their condition, and admit them into Paradise, which He has made known to them. O you who believe! If you help Allah, He will help you and make your feet firm. (Surah Muhammad, 5-7)

Those who follow the Messenger, the Ummi, whom they find written down with them in the Torah and the Gospel, commanding them to do right and forbidding them to do wrong, making good things lawful for them and bad things forbidden for them, relieving them of their heavy loads and the chains that were around them. Those who believe in him, honor him, help him, and follow the Light that has been sent down with him, they are the ones who are successful. (Surat al-A'raf, 157)

Those who were expelled from their homes without any right, merely for saying: "Our Lord is Allah." If Allah had not driven some people back by means of others, monasteries, churches, synagogues, and mosques, in which Allah's name is mentioned much, would have been pulled down and destroyed. Allah will certainly help those who help Him. Allah is All-Strong, Almighty. (Surat al-Hajj, 40)

Before you, We sent other Messengers to their people, and they also brought them the Clear Signs. We took revenge on those who did evil, and it is Our duty to help the believers. (Surat ar-Rum, 47)

The Romans have been defeated in the land nearby, but after their defeat they will be victorious in a few years time. The affair is Allah's from beginning to end. On that day, the believers will rejoice in Allah's help. He grants victory to whomever He wills. He is the Almighty, the Most Merciful. That is Allah's promise. Allah does not break His promise, but most people do not know it. (Surat ar-Rum, 2-6)

Allah will accept prayers

And [mention] the man of the fish [i.e., Yunus], when he left in anger and thought We would not punish him. He called out in the pitch darkness: "There is no god but You! Glory be to You! Truly I have been one of the wrongdoers." We responded to him and rescued him from his grief. That is how We rescue the believers. (Surat al-Anbiya', 87-88)

Nuh called out to Us, and what an excellent Responder We are! We rescued him and his family from the terrible plight. (Surat as-Saffat, 75-76)

Thus does their Lord answer their prayer: "I will not let the deeds of any doer among you go to waste, male or female - you are both the same in that respect. Those who emigrated and were driven from their homes, and suffered harm in My Way and fought and were killed, I will erase their bad actions and admit them into Gardens with rivers flowing under them, as a reward from Allah. The best of all rewards is with Allah." (Surat Al 'Imran, 195)
We responded to him [Ayyub] and removed from him the harm that was afflicting him and restored his family to him, and the same again with them, as a mercy direct from Us and a reminder to all worshippers. (Surat al-Anbiya, 84)

Allah desires ease for believers

As for him who gives out and has fear of Allah and confirms the good, We will pave his way to ease. (Surat al-Layl, 5-7)

Whoever has fear of Allah, He will make matters easy for him. (Surat at-Talaq, 4)

Allah does not demand from any self more than He has given it. Allah will appoint, after difficulty, ease. (Surat at-Talaq, 7)

For truly with hardship comes ease. Truly with hardship comes ease. (Surat al-Inshirah, 5-6)
Allah desires ease for you; He does not desire difficulty for you. [He desires] that you complete the number [of days required in fasting] and proclaim Allah's greatness for the guidance He has given you so that, hopefully, you will be thankful. (Surat al-Baqara, 185)

Allah will have mercy upon His believing servants

He calls down blessings upon you, as do His angels, to bring you out of the darkness into the light. He is Most Merciful to the believers. (Surat al-Ahzab, 43)

The men and women of the believers are friends of one another. They command what is right and forbid what is wrong, establish prayer and pay alms, and obey Allah and His Messenger. They are the people on whom Allah will have mercy. Allah is Almighty, All-Wise. (Surat at-Tawba, 71)