One verse

Srimad Bhagavatam 10.50.5-6

10.50.5-6

निरीक्ष्य तद्ब‍लं कृष्ण उद्वेलमिव सागरम् । स्वपुरं तेन संरुद्धं स्वजनं च भयाकुलम् ॥ ५ ॥ चिन्तयामास भगवान् हरि: कारणमानुष: । तद्देशकालानुगुणं स्वावतारप्रयोजनम् ॥ ६ ॥

nirīkṣya tad-balaṁ kṛṣṇa udvelam iva sāgaram sva-puraṁ tena saṁruddhaṁ sva-janaṁ ca bhayākulam cintayām āsa bhagavān hariḥ kāraṇa-mānuṣaḥ tad-deśa-kālānuguṇaṁ svāvatāra-prayojanam

nirīkṣya
observing
tat
of him (Jarāsandha)
balam
the military force
kṛṣṇaḥ
Lord Kṛṣṇa
udvelam
having overflowed its boundaries
iva
like
sāgaram
an ocean
sva
His own
puram
city, Mathurā
tena
by it
saṁruddham
besieged
sva-janam
His subjects
ca
and
bhaya
by fear
ākulam
disturbed
cintayām āsa
He thought
bhagavān
the Supreme Personality of Godhead
hariḥ
Lord Hari
kāraṇa
the cause of everything
mānuṣaḥ
appearing as a human being
tat
for that
deśa
place
kāla
and time
anuguṇam
suitable
sva-avatāra
of His descent to this world
prayojanam
the purpose

Although Lord Kṛṣṇa, the Supreme Personality of Godhead, is the original cause of this world, when He descended to the earth He played the role of a human being. Thus when He saw Jarāsandha’s assembled army surrounding His city like a great ocean overflowing its shores, and when He saw how this army was striking fear into His subjects, the Lord considered what His suitable response should be according to the time, place and specific purpose of His current incarnation.