First-year teachers face high expectations, challenging demands, and uncertainty during the transition to teaching, which can take an emotional and psychological toll that ultimately saps motivation, undermines self-efficacy, and increases their risk for stress, burnout, and exiting the profession. In this study, I hypothesized that instilling self-compassionate beliefs during the transition to teaching could shift novice teachers’ interpretations of adversity and foster a resilient mindset and growth orientation toward teaching, thereby reducing stress and bolstering well-being, job satisfaction, and commitment to the profession. To instill self-compassionate beliefs, I developed a brief (~30 min) self-compassion training—the first to use social-psychological intervention techniques to impart contemplative insights. To test the efficacy of the training, I conducted a double-blind, randomized controlled longitudinal field experiment with first-year teachers in three teacher education programs. A total of 119 teachers were randomized to receive the training or control activity. There was no evidence for a main effect of training on primary and secondary outcomes. However, significant differential training effects were observed based on teachers’ initial commitment to teaching, initial perceived stress, gender, and teacher education program. The training generated significant positive effects for highly committed teachers (i.e., higher resilient mindset and growth orientation, increases in self-efficacy and job satisfaction, and reductions in burnout, all at 6-month follow-up). However, for teachers low in commitment, the training led to adverse effects on these outcomes. For teachers high in stress, the training led to significant positive effects (i.e., higher growth orientation, declines in perceived stress and increases in self-compassion over the school year). Differential effects by program and gender are also discussed. Findings suggest that a brief psychologically wise training can alter novice teacher beliefs, mindsets, and orientations toward teaching, however, the effects may be beneficial for some groups of teachers and not others. Moving forward, a purposeful investigation should be undertaken to tailor and improve this training to meet the unique range of needs and threats experienced by novice teachers. Research on these types of trainings can inform approaches used in teacher education and induction programming aiming to instill the mindsets and beliefs that promote flourishing in teaching.