If you did not sin, Allah would bring a people who sin so that He may forgive them

It is narrated from Sayyiduna Abu Hurayrah (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "If you did not commit sins, Allah Almighty would bring a people who would commit sins, and Allah would forgive them."
This hadith has a sahih (authentic) chain, but the two Shaykhs did not record it, and the hadith of Sayyiduna Abdullah bin Amr (may Allah be pleased with them both) is a supporting witness (shahid) for it.

It is narrated from Sayyiduna Abdullah bin Amr (may Allah be pleased with them both) that the Prophet (peace and blessings be upon him) said: "If the servants did not commit sins, Allah, the Mighty and Majestic, would create a creation that would commit sins and then He would forgive them, and He is the Oft-Forgiving, the Most Merciful."

It is narrated from Sayyiduna Abu Dharr (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "Allah, the Mighty and Majestic, says: O son of Adam, if you draw near to Me by a hand-span, I will draw near to you by a cubit; and if you draw near to Me by a cubit, I will draw near to you by an arm's length (ba'). O son of Adam, if you intend a good deed in your heart but do not do it, I will record it for you as one good deed; and if you do it, I will record it for you as ten; and if you intend an evil deed and awe of Me holds you back from it, I will record that too as a good deed for you; but if you commit it, I will record it as only one evil deed."
This hadith has a sahih (authentic) chain, and they (the two Shaykhs) did not record it.