In the absolute majority of verses of the Quran, it is said that only believers who have done righteous deeds will get to Heaven:

> And give good tidings to those who believe and do righteous deeds that
> they will have gardens [in Paradise] beneath which rivers flow.
> Whenever they are provided with a provision of fruit therefrom, they
> will say, "This is what we were provided with before." And it is given
> to them in likeness. And they will have therein purified spouses, and
> they will abide therein eternally. ([2] Al-Baqarah : 25)

> And whoever does righteous deeds, whether male or female, while being
> a believer – those will enter Paradise and will not be wronged, [even
> as much as] the speck on a date seed. ([4] An-Nisa : 124)

But there are verses saying the opposite. There aren't many of them, but I can't understand them. For example, in Sura 9, verse 72, believers without righteous deeds are already mentioned, and it is said that Paradise is promised to them.

> Allah has promised the believing men and believing women gardens
> beneath which rivers flow, wherein they abide eternally, and pleasant
> dwellings in gardens of perpetual residence; but approval from Allah
> is greater. It is that which is the great attainment. ([9] At-Tawbah :
> 72)

At 33:44 there is also a similar:

> Their greeting the Day they meet Him will be, "Peace." And He has
> prepared for them a noble reward. ([33] Al-Ahzab : 44)

I have heard hadiths where it is said that Muslims who have gone to Hell for their sins will eventually come out of there. But according to the Koran, it would be wrong, because it says:

> And you will see them being exposed to it [i.e., the Fire], humbled
> from humiliation, looking from [behind] a covert glance. And those who
> had believed will say, "Indeed, the [true] losers are the ones who
> lost themselves and their families on the Day of Resurrection.
> Unquestionably, **the wrongdoers are in an enduring punishment**." ([42]
> Ash-Shuraa : 45)

As a result, why is the word "righteous deeds" omitted in 9:72 and why does it say that all believers will go to Heaven, while in other verses righteous deeds are obligatory? And how to explain verse 42:45, which says that sinners will be in Hell forever, regardless of faith?