SB 5.10.4

na vayaṁ nara-deva pramattā bhavan-niyamānupathāḥ sādhv eva vahāmaḥ. ayam adhunaiva niyukto ’pi na drutaṁ vrajati nānena saha voḍhum u ha vayaṁ pārayāma iti.
Synonyms: 
na — not; vayam — we; nara-deva — O lord among human beings (the king is supposed to be the representative of deva, the Supreme Personality of Godhead); pramattāḥ — neglectful in our duties; bhavat-niyama-anupathāḥ — who are always obedient to your order; sādhu — properly; eva — certainly; vahāmaḥ — we are carrying; ayam — this man; adhunā — just recently; eva — indeed; niyuktaḥ — being engaged to work with us; api — although; na — not; drutam — very quickly; vrajati — works; na — not; anena — him; saha — with; voḍhum — to carry; u ha — oh; vayam — we; pārayāmaḥ — are able; iti — thus.
Translation: 
O lord, please note that we are not at all negligent in discharging our duties. We have been faithfully carrying this palanquin according to your desire, but this man who has been recently engaged to work with us cannot walk very swiftly. Therefore we are not able to carry the palanquin with him.
Purport: 

The other palanquin carriers were śūdras, whereas Jaḍa Bharata was not only a high-caste brāhmaṇa but also a great devotee. Śūdras do not sympathize with other living beings, but a Vaiṣṇava cannot act like a śūdra. Whenever a śūdra and a brāhmaṇa Vaiṣṇava are combined, there will certainly be imbalance in the execution of duties. The śūdras were walking with the palanquin without at all caring for the ants on the ground, but Jaḍa Bharata could not act like a śūdra, and therefore difficulty arose.