How can we judge by conjecture that a Hadith is a lie, when Allah Almighty says: "Indeed, conjecture avails not against the truth at all," along with the Hadith: "Whoever narrates a Hadith from me, believing it to be a lie, is one of the two liars"?

The hadith: "Whoever narrates a hadith from me that is thought to be a lie, then he is one of the liars," warns against attributing a hadith to the Prophet, peace and blessings be upon him, when one suspects it to be false, and mandates verifying the hadith before narrating it. Al-Nawawi said: It is forbidden to narrate a fabricated hadith for anyone who knows or strongly suspects its fabrication. The infiltration of doubts into the heart is a serious matter, for as Ibn al-Qayyim said about his shaykh Ibn Taymiyyah: Do not make your heart like a sponge that absorbs doubts, but rather like a solid glass through which doubts pass without settling therein.