The word(s) "vast" appears 6 time(s) in 6 verse(s) in Quran in Mohsin Khan translation.

(1) If they (Jews) belie you (Muhammad صلى الله عليه وسلم) say: "Your Lord is the Owner of vast Mercy, and never will His Wrath be turned back from the people who are Mujrimun (criminals, polytheists or sinners)."

(2) Truly Allah has given you victory on many battle fields, and on the Day of Hunain (battle) when you rejoiced at your great number, but it availed you naught and the earth, vast as it is, was straitened for you, then you turned back in flight.

(3) And (He did forgive also) the three [who did not join the Tabuk expedition whose case was deferred (by the Prophet صلى الله عليه وسلم)] (for Allah's Decision) till for them the earth, vast as it is, was straitened and their ownselves were straitened to them, and they perceived that there is no fleeing from Allah, and no refuge but with Him. Then, He forgave them (accepted their repentance), that they might beg for His pardon [repent (unto Him)] Verily, Allah is the One Who forgives and accepts repentance, Most Merciful.

(4) Or [the state of a disbeliever] is like the darkness in a vast deep sea, overwhelmed with waves topped by waves, topped by dark clouds, (layers of) darkness upon darkness: if a man stretches out his hand, he can hardly see it! And he for whom Allah has not appointed light, for him there is no light.

(5) With power did We construct the heaven. Verily, We are Able to extend the vastness of space thereof.

(6) Those who avoid great sins (See the Qur'an, Verses: 6:152,153) and Al-Fawahish (illegal sexual intercourse) except the small faults, - verily, your Lord is of vast Forgiveness. He knows you well when He created you from the earth (Adam), and when you were fetuses in your mothers' wombs. So ascribe not purity to yourselves. He knows best him who fears Allah and keeps his duty to Him [i.e. those who are Al-Muttaqun (the pious. See V.2:2)].