Therefore, to bring the neophyte devotees to the perfectional stage, we offer the brahmana's sacred thread. But if people, after promising everything, and break their promise, that is very abominable. When they're initiated before the Deity, before the Lord, before the fire, they should not break it. That is most sinful if you break your promise. Otherwise, you should not be coming forward for initiation if you cannot keep your promise.
>>> Ref. VedaBase => Srimad-Bhagavatam 1.16.20 — Hawaii, January 16, 1974