Large Language Models (LLMs) can justify or criticize their predictions through discussion with other models or humans, thereby enhancing their intrinsic understanding of instances. While proactive discussions enhance performance, this approach is currently limited to the inference phase. In this context, we posit a hypothesis: learning interactive discussions during training can improve understanding for the instances in the training step and proficiency in logical/critical thinking ability and verbalized expression of the model in the inference step. Our proposed SAIE training method involves both supportive and adversarial discussions between the learner and partner models. The learner model receives a remark from the partner through the discussion, and the parameters of the learner model are then updated based on this remark. That is, the teacher signal dynamically adjusts in response to the evolving model output throughout the training step. By bolstering the capacity for discussion and comprehension of instances, our experiments across datasets, including GSM8K, CommonsenseQA, and MMLU, reveal that models fine-tuned with our method consistently surpass those trained with standard fine-tuning techniques. Moreover, our approach demonstrates superior performance in multi-agent inference scenarios, boosting the models' reasoning abilities at the inference step.