# cross my heart

idiom

Source: https://englishreference.com/idiom/cross-my-heart
Updated: 2026-08-10

## Meaning

A declaration that the speaker is telling the truth.

## Examples

- I will return your book tomorrow, cross my heart.
- I am telling the truth about the money, cross my heart.
- I cross my heart that I will be there to help you move.
- I did not break your favorite vase, cross my heart and hope to die.
- I promise to keep your secret safe and won't tell anyone at the office, cross my heart.
- You can trust me to pick up the kids on time today, cross my heart and hope to die.
- I have no idea who ate your lunch from the shared fridge, cross my heart, because I brought my own meal today.
- She looked him directly in the eyes and, cross my heart, swore that she had never seen the missing documents before that moment.

## Origin

A shortened form of the oath "cross my heart and hope to die," with the physical gesture of making the sign of the cross over the chest serving as a silent witness to one's sincerity. While the full phrase is not recorded in print until the mid-19th century, the truncated version serves as a verbal shorthand for the same underlying commitment to the truth, however precarious.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.