Be cautious both when you are joyful and when you are sorrowful

My child, be cautious both when you are joyful and when you are sorrowful. When you are joyful, you should not lose restraint due to liveliness and laughter; nor should you, when sorrowful, become so downcast that it is noticeable. This happens because Satan strikes us with thoughts as with arrows, but he cannot conquer us unless our heart is receptive to them.

However, he is very cunning. When he casts an arrow—when he attacks us with an evil thought—he observes our face and every movement of our body. Based on this, he evaluates how well the arrow has struck our heart. 

Therefore, when you are joyful, you should conceal it within yourself so that he does not uncover your carelessness and rob you through some temptation. Likewise, when you are sorrowful, do not reveal it to him, for if he discerns the cause of your sorrow, he will increase your pain. If you manage to remain balanced both in joy and in sorrow, the devil will not be able to discern what is happening within you, and he will not know how to fight against you. 

+ Elder Ephraim of Arizona - https://www.holyresurrection.shop/