[They will be] reclining (muttaki’īna is a circumstantial qualifier referring to the concealed subject of God’s words fī jannātin, ‘amid gardens’) on ranged couches, [arranged] one next to the other, and We will wed them (zawwajnāhum is a supplement to jannātin, ‘gardens’, meaning ‘We will couple them’) to beautiful houris, of wide and beautiful eyes.
Allah the Exalted described the destination of the happy ones,
إِنَّ الْمُتَّقِينَ فِى جَنَّـتٍ وَنَعِيمٍ
(Verily, those who have Taqwa will be in Gardens and Delight.) in contrast to the torment and punishment of the miserable;
فَـكِهِينَ بِمَآ ءَاتَـهُمْ رَبُّهُمْ
(Enjoying in that which their Lord has bestowed on them,) meaning, enjoying the various types of delight that Allah has granted them therein, such as various types of foods, drinks, clothes, dwelling places, mounts, and so forth,
وَوَقَـهُمْ رَبُّهُمْ عَذَابَ الْجَحِيمِ
(and (the fact that) their Lord saved them from the torment of the blazing Fire.) He saved them from the torment of the Fire, which is a bounty itself. Added to this blessing is the fact that they were entered into Paradise, which has delights that no eye has ever seen, no ear has ever heard, nor has a heart ever imagined. The statement of Allah the Exalted,
(Eat and drink at ease for that which you have sent on before you in days past!)(69:24) meaning this is the just reward for your deeds; surely, all this is a favor from Allah and a reward from Him. Allah the Exalted said,
مُتَّكِئِينَ عَلَى سُرُرٍ مَّصْفُوفَةٍ
(They will recline (with ease) on thrones Masfufah.) Ath-Thawri reported from Husayn, from Mujahid, from Ibn `Abbas: "Thrones in howdahs.'' And the meaning of, (Masfufah) is they will be facing each other,
عَلَى سُرُرٍ مُّتَقَـبِلِينَ
(Facing one another on thrones.)(37:44) Allah said next,
وَزَوَّجْنَـهُم بِحُورٍ عِينٍ
(And We shall marry them to Hur (fair females) with wide lovely eyes.) We made for them righteous spouses, beautiful wives from Al-Hur Al-`Ayn. We mentioned the description of Al-Hur Al-`Ayn in several other places in this Tafsir, and therefore, it is not necessary to repeat their description here.
Maududi - Sayyid Abul Ala Maududi - Tafhim al-Qur'an
"The righteous" : the people who believed in the news given by the Prophets and who safeguarded themselves in the world itself and refrained from thoughts and deeds that doom man to Hell.
There seems to be no need to mention a person's being saved from Hell after it has been said that he will be admitted to Heaven, but at several places in the Qur'an these two things have been mentioned separately because a person's being saved from Hell is by itself a great blessing. And the words, "their Lord shall save them from the torment of Hell", is an allusion to the truth that man's being saved from Hell is possible only through Allah's grace and bounty; otherwise human weaknesses cause such flaws to occur in everyone's work that if Allah does not overlook them by His grace and instead decides to subject him to accountability, none can save himself from His punishment. That is why although entry into Paradise is a great bounty from Allah, his being saved from Hell is no less a mercy.
Here, the word "with relish" contains vast meaning in itself. In Paradise whatever a man receives, he will have it without any labor and toil. There will be no question of its sustenance in short supply. Man will not have to spend anything for it. It will be precisely according to his desire and choice and taste. In whatever quantity and whenever he will desire it, it will be made available. He will not be staying there as a guest that he may feel shy of asking for something, but everything will be the reward of his lifelong deeds and the fruit of his own labors. His eating and drinking anything will not cause any illness nor will he eat for satisfying hunger or for survival but only for the sake of enjoyment. Man will be able to obtain as much pleasure from it as he pleases without the fear of indigestion, and the food eaten will not produce any filth. Therefore, the meaning of eating and drinking "with relish" in Paradise is much mere vast and sublime than what is understood by it in the world.
For explanation, see E. N. 's 20, 29 of Surah As-Saaffat, and E. N. 42 of Ad-Dukhan.