On the authority of Anas [R.A] who said I heard the Messenger of Allah saying, Allah the Almighty has said:
"O son of Adam, as long as you call upon 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 as great as the earth and were you then to face Me, ascribing no partner to Me, I would grant you forgiveness as great as it."
Imam Shafi' said:
You belittle to supplicate
And ignore its fruit
It is like an arrow, great
But! Night's arrows do not fail
It has a definite span
That is duly faint
All other explanation inside the book.
All praise is due to Allah Ta'ala, The Supreme Master of all the worlds. Countless Durood and Salaam be upon our beloved Nabi, Sayyidina Muhammad( PBUH ).