Hadith Qudsi 9:
On the authority of Abu Harayrah (may Allah be pleased with him) from the Prophet (PBUH), who said: Allah (mighty and sublime be He) says:

The fist of his actions for which a servant of Allah will be held accountable on the Day of Resurrection will be his prayers. If they are in order, then he will have prospered and succeeded: and if they are wanting, then he will have failed and lost. If there is something defective in his obligatory prayers, the Lord (glorified and exalted be He) will say: See if My servant has any supererogatory prayers with which may be completed that which was defective in his obligatory prayers. Then the rest of his actions will be judged in like fashion.

It was related by at-Tirmidhi (also by Abu Dawud, an-Nasa’i, Ibn Majah and Ahmad).

Hadith Qudsi 15:
On the authority of Abu Harayrah (may Allah be pleased with him), who said that the Prophet (PBUH) said: Allah the Almighty said:

I am as My servant thinks I am (1). I am with him when he makes mention of Me. If he makes mention of Me to himself, I make mention of him to Myself; and if he makes mention of Me in an assembly, I make mention of him in an assemble better than it. And if he draws near to Me an arm’s length, I draw near to him a fathom’s length. And if he comes to Me walking, I go to him at speed.

(1) Another possible rendering of the Arabic is: “I am as My servant expects Me to be”. The meaning is that forgiveness and acceptance of repentance by the Almighty is subject to His servant truly believing that He is forgiving and merciful. However, not to accompany such belief with right action would be to mock the Almighty.

It was related by al-Buhkari (also by Muslim, at-Tirmidhi and Ibn-Majah).

Hadith Qudsi 34:
On the authority of Anas (may Allah be pleased with him), who said: I heard the Messenger of Allah (PBUH) say: Allah the Almighty said:

O son of Adam, so long as you call upon Me and ask of Me, I shall forgive you for what you have done, and I shall not mind. O son of Adam, were your sins to reach the clouds of the sky and were you then to ask forgiveness of Me, I would forgive you. O son of Adam, were you to come to Me with sins nearly as great as the earth and were you then to face Me, ascribing no partner to Me, I would bring you forgiveness nearly as great at it.

It was related by at-Tirmidhi (also by Ahmad ibn Hanbal). Its chain of authorities is sound.

Hadith Qudsi 35:
On the authority of Abu Hurayrah (may Allah be pleased with him), who said that the Messenger of Allah (PBUH) said:

Our Lord (glorified and exalted be He) descends each night to the earth’s sky when there remains the final third of the night, and He says: Who is saying a prayer to Me that I may answer it? Who is asking something of Me that I may give it him? Who is asking forgiveness of Me that I may forgive him?

It was related by al-Bukhari (also by Muslim, Malik, at-Tirmidhi and Abu Dawud).

In a version by Muslim the Hadith ends with the words:

And thus He continues till [the light of] dawn shines.

http://www.usc.edu/schools/college/crcc/engagement/resources/texts/muslim/hadith/hadithqudsi.html