Is "If you knew the extent of Allah's mercy, you would rely upon it" an authentic Prophetic hadith?

The Hadith: "If you knew the extent of Allah's mercy, you would rely solely on it and do no deeds; and if you knew the extent of His wrath, nothing would benefit you," has a weak chain of narration due to its reliance on weak narrators. However, its meaning is corroborated by other traditions.

Indeed, it is narrated in Sahih Muslim and Al-Bukhari that the Prophet (peace be upon him) said: "Allah created mercy on the day He created it into one hundred parts. He withheld ninety-nine parts with Himself and sent down to all His creation one single part. If the disbeliever knew all the mercy that is with Allah, he would not despair of Paradise. And if the believer knew all the punishment that is with Allah, he would not feel secure from the Fire."

The purpose of these Ahadith is for a person to be in a state between fear and hope. One should neither be excessive in hope nor in fear, but rather combine them to perfect one's deeds. "And invoke Him with fear and hope. Indeed, the mercy of Allah is near to the doers of good." (Al-A'raf: 56)