Which verses of the Quran and which hadiths explained verse 50:35: {They will have whatever they wish therein, and with Us is more.}?

All perfect praise be to Allaah, The Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad is His slave and Messenger.

There are similar verses in this regard, such as the saying of Allaah (which means): {For them who have done good is the best [reward] and extra.} [Quran 10:26]; and the saying of Allaah (which means): {That Allaah may reward them [according to] the best of what they did and increase them from His bounty.} [Quran 24:38]

Besides, Suhayb narrated that the Prophet said, “When those deserving of Paradise will enter Paradise, Allaah, The Exalted, will ask, ‘Do you wish Me to give you anything more?’ They will say, ‘Have You not brightened our faces? Have You not made us enter Paradise and saved us from Hellfire?’” He (the Messenger of Allaah) said, “He (Allaah) will lift the veil, and of all the things given to them, nothing will be dearer to them than looking at (seeing) their Lord.” Then he recited the verse {For them who have done good is the best [reward] and extra.} [Quran 10:26] [Muslim]

The prominent scholar Shaykh Al-Ameen Ash-Shinqeeti said in Adh-waa’ Al-Bayaan fi Eedhaah Al-Quran bil-Quran, “Regarding the saying of Allaah in this verse: {and with Us is more} [Quran 50:35], some scholars said, ‘More means looking at the Face of Allaah, the Glorious;’ what also proves this is the saying of Allaah {For them who have done good is the best [reward] and extra.} [Quran 10:26] because ‘the best reward’ is Paradise, and the ‘extra’ means looking (at Allaah), and Allaah knows best.”

If you need more elaboration on this, then you may refer to the books of Tafseer (interpretation of the Quran) that interpret the Quran by the authentic ahaadeeth of the Prophet .

Allaah knows best.