SB 10.5.19

gopān gokula-rakṣāyāṁ
 nirūpya mathurāṁ gataḥ
nandaḥ kaṁsasya vārṣikyaṁ
 karaṁ dātuṁ kurūdvaha
Word for word: 
gopān — the cowherd men; gokula-rakṣāyām — in giving protection to the state of Gokula; nirūpya — after appointing; mathurām — to Mathurā; gataḥ — went; nandaḥ — Nanda Mahārāja; kaṁsasya — of Kaṁsa; vārṣikyam — yearly taxes; karam — the share of profit; dātum — to pay; kuru-udvaha — O Mahārāja Parīkṣit, best protector of the Kuru dynasty.
Translation: 
Śukadeva Gosvāmī continued: Thereafter, my dear King Parīkṣit, O best protector of the Kuru dynasty, Nanda Mahārāja appointed the local cowherd men to protect Gokula and then went to Mathurā to pay the yearly taxes to King Kaṁsa.
Purport: 

Because the killing of babies was going on and had already become known, Nanda Mahārāja was very much afraid for his newborn child. Thus he appointed the local cowherd men to protect his home and child. He wanted to go immediately to Mathurā to pay the taxes due and also to offer some presentation for the sake of his newborn son. For the protection of the child, he had worshiped various demigods and forefathers and given charity to everyone’s satisfaction. Similarly, Nanda Mahārāja wanted not only to pay Kaṁsa the yearly taxes but also to offer some presentation so that Kaṁsa too would be satisfied. His only concern was how to protect his transcendental child, Kṛṣṇa.