Narada Purana (Jyotisha Selections) · by Vyasa
Chapter 7 · Samskara Muhurtas
संस्कारमुहूर्ताः
शुभनवांशकगता ग्राह्यास्ते शुभराशयः ।न कदाचित्कर्कटांशशुभेक्षितयुतोऽपि वा ॥ ३७३ ॥
In the full Narada Purana (Purva Bhaga) this is chapter 56, verse 373.
Those good signs are to be taken that sit in a good navamsha (one-ninth part of a sign). Never one in a Cancer navamsha, even if joined or looked at by good planets.
Simple meaning: Take signs in a good navamsha. Never take a Cancer navamsha, even with good planets looking.
तस्माद्गोमिथुनांशाश्च तुलाकन्यांशकाः शुभाः ।
Taurus, Gemini, Libra and Virgo navamshas are good for the thread ceremony.
त्रिषडायगतैः पापैः षडष्टांत्यविवर्जितैः ।
Bad planets in the 3rd, 6th or 11th. Good planets away from 6, 8, 12. Moon away from 6, 8, 12, 1.
स्वोच्चसंस्थोऽपि शीतांशुर्व्रतिनो यदि लग्नगः ।
Even an exalted Moon in the rising sign can make the boy poor and sickly.