The expression "sware god" is often used to emphasize the truthfulness of a statement or promise. However, not everyone may feel comfortable using religious references in their language. There are plenty of alternative phrases that can be used to convey the same sentiment. "I swear on my life" or "I swear on everything I hold dear" both suggest a strong commitment to honesty. Other options might include "cross my heart" or "I solemnly swear." Ultimately, the key is to choose a phrase that feels authentic and meaningful to you, without relying on religious language if it doesn't align with your personal beliefs.