The doors of liberation are opened wide to one who has achieved human life. But if a human being simply devotes himself to family life like the foolish bird in this story, then he is to be considered as one who has climbed to a high place only to trip and fall down.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
यः प्राप्य मानुषं लोकं मुक्तिद्वारमपावृतम् । गृहेषु खगवत्सक्तस्तमारूढच्युतं विदुः
yaḥ prāpya mānuṣaṃ lokaṃ muktidvāramapāvṛtam | gṛheṣu khagavatsaktastamārūḍhacyutaṃ viduḥ
SB 11.7.74