Agni Purana (Jyotisha Selections) · by Vyasa
Chapter 5 · Omens
शकुनानि
विद्विष्टनाशकं सैन्यं संभूतान्तःप्रकोपनम् ।शरीरस्फुरणे धन्ये तथा सुस्वप्नदर्शने ॥ ४ ॥
In the full Agni Purana this is chapter 228, verse 4.
One may march when one's army can destroy the hated foe. Or when a revolt has broken out inside the enemy's camp. Also when a body twitch is good, and when good dreams are seen.
Simple meaning: March when your army is strong, the enemy faces revolt, and twitches and dreams are good.
निमित्ते शकुने धन्ये जाते शत्रुपुरं व्रजेत् ।
On good omens, go against the enemy city. In the rains, send an army of foot soldiers and elephants.
सेना पदातिबहुला शत्रूञ्जयति सर्वदा ।
An army strong in foot soldiers wins. A twitch on the right side of the body is good.
न शस्तं तु तथा वामे पृष्ठस्य हृदयस्य च ।
Twitches and marks on the left are not good for men. For women the left side is good.