ثَقُلَتْ

Appears 4 times in the Quran. (Root: ثقل)
  1. And the measuring out on that day will be just; then as for him whose measure (of good deeds) is heavy, those are they who shall be successful;

  2. They ask you about the hour, when will be its taking place? Say: The knowledge of it is only with my Lord; none but He shall manifest it at its time; it will be momentous in the heavens and the earth; it will not come on you but of a sudden. They ask you as if you were solicitous about it. Say: Its knowledge is only with Allah, but most people do not know.

  3. Then as for him whose good deeds are preponderant, these are the successful.

  4. Then as for him whose measure of good deeds is heavy,