40. On account of the trembling.
In the part of the Katha-Upanishad which intervenes between the passage 'The Person of the size of a thumb
stands in the middle of the Self (II, 4, 12), and the passage 'The Person of the size of a thumb, the inner Self' (II, 6, 17), we meet with the text 'whatever there is, the whole world, when gone forth, trembles in its breath. A great terror, a raised thunderbolt; those who knew it became immortal. From fear of it fire burns, from fear the sun shines, from fear Indra and Vâyu, and Death as the fifth run away' (II, 6, 2; 3). This text declares that the whole world and Agni, Sûrya, and so on, abiding within that Person of the size of a thumb, who is here designated by the term 'breath,' and going forth from him, tremble from their great fear of him. 'What will happen to us if we transgress his commandments ?'--thinking thus the whole world trembles on account of great fear, as if it were a raised thunderbolt. In this explanation we take the clause 'A great fear, a raised thunderbolt,' in the sense of '(the world trembles) from great fear,' &c., as it is clearly connected in meaning with the following clause: 'from fear the fire burns,' &c.--Now what is described here is the nature of the highest Brahman; for that such power belongs to Brahman only we know from other texts, viz.: 'By the command of that Imperishable, O Gârgî, sun and moon stand apart' (Bri. Up. III, 8, 9); and 'From fear of it the wind blows, from fear the sun rises; from fear of it Agni and Indra, yea Death runs as the fifth' (Taitt. Up. II, 8, 1).--The next Sûtra supplies a further reason.