And the Noble Prophet (peace and blessings be upon him) said: Allah Almighty says, if My servant intends to do a good deed, I write it as one good deed for him. Then if he acts upon it, I write it increased tenfold. And if he intends to commit a sin, I do not write it. If he commits the sin, I write only one sin.
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 8166