Abu Huraira reported Allah's Messenger (ﷺ) as saying:
A bulky person would be brought on the Day of judgment and he would not carry the weight to the eye of Allah equal even to that of a gnat. Nor shall We set up a balance for them on the Day of Resurrection" (xviii. 105).
Reference: Sahih Muslim 2785
In-book reference: Book 52, Hadith 1
USC-MSA web (English) reference(deprecated numbering scheme): Book 39, Hadith 6698