पार्थमाप्याययन् स्वेन तेजसाचिन्तयद्धरि: ॥ ४० ॥
jīvitaṁ ca jarā-kṛtam
pārtham āpyāyayan svena
śatroḥ — of the enemy; janma — the birth; mṛtī — and death; vidvān — knowing; jīvitam — the bringing to life; ca — and; jarā — by the demoness Jarā; kṛtam — done; pārtham — Bhīma, the son of Pṛthā; āpyāyayan — empowering; svena — with His own; tejasā — potency; acintayat — thought; hariḥ — Lord Kṛṣṇa.
Lord Kṛṣṇa knew the secret of His enemy Jarāsandha’s birth and death, and also how he had been given life by the demoness Jarā. Considering all this, Lord Kṛṣṇa imparted His special power to Bhīma.
Śrīla Prabhupāda writes that Lord Kṛṣṇa “knew the mystery of the birth of Jarāsandha. Jarāsandha was born in two different parts from two different mothers. When his father saw that the baby was useless, he threw the two parts in the forest, where they were later found by a black-hearted witch named Jarā. She managed to join the two parts of the baby from top to bottom. Knowing this, Lord Kṛṣṇa therefore also knew how to kill him.”