A Time for Fear and a Time for Love

Gemara: Rav Ashi said: I witnessed the following practice of Rav Kahana: When there was pain in the world, he would remove his cloak, clench up his hands, and daven. He would say that this is like a servant before his master. When there was peace in the world, he would wear [nice clothing], wrap himself [in a cloak], and then daven. He would say that [this fulfills the pasuk] "Prepare for approaching your G-d, O Israel" (Amos 4:12).

Ein Ayah: Fear and love are two emotions that a person has to acquire in order to walk on the pure path of Hashem. The broad results of fear are the lowering of one’s spirit and the retreat in one’s efforts so that one will not burst forth beyond his boundaries and thereby damage the good path. This is the opposite of the effect of love, which expand one’s powers so that he can accomplish ever-increasing good things.
One cannot know exactly how to create the proper balance between the different emotions he should cultivate. At what times should he focus on internalizing fear of Hashem? When should he focus on love of Hashem, which widens the heart?
The best idea is to take a look at the standing of the broad community and to see how Hashem is acting toward the world. There can be great swings in the mood. Sometimes there is a spirit of happiness and excitement, and sometimes there are stormy times that contain frightening circumstances. An individual should view himself as part of the general situation of the world, at least that part of the world that is close to him. The situation around him should be the greatest indicator of whether it is appropriate to focus on a fear that serves as a roadblock to powers of evil, or whether he should increase acquisition of love that expands his positive powers.
When there is pain in the world, this is a sign that there had been a lacking in those characteristics that are related to pain in the generation. Rav Kahana would then clench his hands and remove his cloak before davening to stress that it was necessary to increase the level of fear. When there was peace in the world, it was time to expand the powers of goodness. At that time he would "wear" happiness and cloak himself in clothes of honor and grandeur. This was to widen his heart, increase the vigor in performing good deeds, and expand the completeness of the mind and the light of Hashem. He did this in the spirit of "Prepare for approaching your G-d, O Israel."