Rashi: They are Chachamim.

Orchos Tzadikim (Sha'ar ha'Atzlus DH Re'eh): If a king has many messengers, and all do his missions and report to him when they return, and one of them was lazy, and schemed to say 'I am ill!' He eats at the king's table, and when he sees them exerting, he considers himself wiser than all his colleagues. This is folly! "Chazisa Ish Mahir bi'Mlachto Lifnei Melachim Yisyatzav" (22:29). The king will pay the clever ones, who returned and reported to him.

Mesilas Yesharim (Perek 6): They are people who rebuke him. Laziness does not let him be concerned for their words. He thinks that all err and are fools, and he alone is wise.

Malbim: They are great Chachamim, who answer him the reason for matters and their content. It seems to him that he is a greater Chacham than them; there is more hope for a Kesil than for him (12).