Abdullah ibn Mubaarak 171 AH (may Allah have mercy on him) said,

رب عمل صغير تعظمه النية و رب عمل كبير تصغره النية

“Perhaps a small deed becomes great because of the intention behind it, and perhaps a big deed becomes insignificant because of the intention behind it.”

Taken from Jaami’ ‘Uloom p. 16