"Labbayk" (لبّيك) is an Arabic phrase commonly associated with the Islamic pilgrimage of Hajj. It is often translated as "Here I am" or "At your service" in English. While the exact phrase "Labbayk" may not be explicitly mentioned in the Quran, the concept of responding to the call of Allah is emphasized in several verses.
One relevant verse is from Surah Al-Baqarah (2:196), where Allah says:
"And complete the Hajj and Umrah for Allah. But if you are prevented, then [offer] what can be obtained with ease of sacrificial animals. And do not shave your heads until the sacrificial animal has reached its place of slaughter. And whoever among you is ill or has an ailment of the head [making shaving necessary must offer] a ransom of fasting [three days] or charity or sacrifice. And when you are secure, then whoever performs 'Umrah [during the Hajj months] followed by Hajj [offers] what can be obtained with ease of sacrificial animals. And whoever cannot find [or afford such an animal] - then a fast of three days during Hajj and of seven when you have returned [home]. Those are ten complete [days]. This is for those whose family is not in the area of al-Masjid al-Haram. And fear Allah and know that Allah is severe in penalty."
While this verse doesn't directly mention "Labbayk," it speaks to the completion of Hajj and Umrah for the sake of Allah, which is the essence of the Labbayk response – responding to the call of Allah to perform the pilgrimage.