How can a Muslim balance between his pride and humility, or differentiate between self-confidence and arrogance, especially since humility may be viewed as weakness and confidence as arrogance?

A Muslim is required to be proactive and to exert effort, then to entrust all matters to Allah Almighty. Self-confidence, after relying on Allah, is Islamically required, and it is an appraisal of available capabilities, not the blameworthy arrogance, which is a feeling of grandeur and an illusion of perfection. Humility is a praiseworthy characteristic and does not contradict self-confidence. The Prophet, peace and blessings be upon him, was humble, courageous, and confident in Allah. Humility is the opposite of pride (kibr), which is rejecting the truth and despising people, not the opposite of self-confidence.