This study aimed to examine the motivations and behaviors of spiritual-themed tourists in Nakhon Si Thammarat Province using a quantitative research approach. The sample consisted of 400 tourists who engaged in spiritual tourism, with data collected through questionnaires and analyzed using both descriptive and inferential statistics. The findings revealed that: (1) demographic factors—such as gender, age, education level, occupation, average income, religion, and place of origin—were significantly associated with spiritual tourism behavior; (2) both intrinsic and extrinsic motivations were significantly related to spiritual tourism behavior. Key intrinsic motivations included the desire to pay respect for peace of mind and personal spiritual development, while major extrinsic motivations involved social media influence and popular trends; and (3) spiritual tourism behaviors observed included traveling to seek blessings for career success, traveling 2–3 times per year, traveling with family, and spending at a moderate level during trips. These findings are beneficial for planning and developing spiritual tourism to better meet the needs of contemporary travelers and to promote sustainable tourism growth.