How sound is the Hadith: "Indeed, Allah forgives major sins, so do not despair; and He punishes for minor sins, so do not be overconfident"?

There is no hadith with this wording narrated from the Prophet, peace and blessings be upon him, but its meaning is sound, which is that a Muslim must combine in their heart the fear of Allah's punishment and the hope for His mercy and forgiveness. This meaning has been indicated by texts from the Holy Quran and the Prophetic Sunnah, such as the Almighty's saying: (Call upon your Lord humbly and privately; indeed, He does not like transgressors. And do not cause corruption upon the earth after its reformation. And invoke Him in fear and hope. Indeed, the mercy of Allah is near to the good-doers.) [Quran 7:55-56]. Similarly, the texts have warned against despair and hopelessness concerning Allah's mercy, and against feeling secure from His planning.