Dua.

Quran

وَإِذَا سَأَلَكَ عِبَادِي عَنِّي فَإِنِّي قَرِيبٌۖ أُجِيبُ دَعۡوَةَ ٱلدَّاعِ إِذَا دَعَانِۖ فَلۡيَسۡتَجِيبُواْ لِي وَلۡيُؤۡمِنُواْ بِي لَعَلَّهُمۡ يَرۡشُدُونَ

And when My servants ask you, [O Muhammad], concerning Me – indeed I am near. I respond to the invocation of the supplicant when he calls upon Me. So let them respond to Me [by obedience] and believe in Me that they may be [rightly] guided.

[Surah Al-Baqarah 186]

Hadith

عَنْ جُبَيْرِ بْنِ نُفَيْرٍ، أَنَّ عُبَادَةَ بْنَ الصَّامِتِ، حَدَّثَهُمْ أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ

‏ مَا عَلَى الأَرْضِ مُسْلِمٌ يَدْعُو اللَّهَ بِدَعْوَةٍ إِلاَّ آتَاهُ اللَّهُ إِيَّاهَا أَوْ صَرَفَ عَنْهُ مِنَ السُّوءِ مِثْلَهَا مَا لَمْ يَدْعُ بِمَأْثَمٍ أَوْ قَطِيعَةِ رَحِمٍ ‏”‏ ‏.‏ فَقَالَ رَجُلٌ مِنَ الْقَوْمِ إِذًا نُكْثِرَ ‏.‏ قَالَ ‏”‏ اللَّهُ أَكْثَرُ ‏”‏ ‏
رواه الترمذي ٣٥٧٣ وقال هَذَا حَدِيثٌ حَسَنٌ صَحِيحٌ غَرِيبٌ مِنْ هَذَا الْوَجْهِ

‏ ‏‏

Jubair bin Nufair narrated that `Ubadah bin As-Samit narrated to them that, the Messenger of Allah (ﷺ) said:

“There is not a Muslim upon the earth who calls upon Allah with any supplication, except that Allah grants it to him, or he turns away from him the like of it in evil; as long as he does not supplicate for something sinful, or the severing of the ties of kinship.”

So a man from the people said:
“What if we should increase (in it)”

He (ﷺ) said: “(With) Allah is more.”

Jami` at-Tirmidhi 3573