What is the ruling on using weak hadiths as evidence in da'wah?

Question:
May Allah reward you, Honorable Shaykh. This questioner asks: Is it permissible to use weak hadiths as evidence in calling people to Allah the Exalted?

Answer:
The scholars have clarified this and said that weak hadiths are not all the same. Some are weak but have corroborating narrations that strengthen them, so they rise to the level of hasan li-ghayrihi. Others are weak with no corroborating narrations, so they remain weak, but their weakness is not extreme. So, the weak hadith is roughly divided into three categories. The first is a weak hadith with corroborating narrations that raises it to the degree of hasan; this is accepted. The second is a weak hadith with no corroborating narrations, but it is not severely weak; this is used as evidence for the virtues of deeds, but no ruling is established by it, and no permission or prohibition is built upon it; it is only used as evidence for encouraging good and warning against evil.
Yes. And the third is a hadith that is severely weak; this is not acted upon and is not used as evidence. Yes.