In Ps 73:18 'When I thought to know this, it was too painful for me' as well as in 2Es 7:12, 2Ma 2:26 'painful' means 'laborious': and so 'painfulness' in 2Co 11:27 means 'Iahoriousness.' Hooker says, 'The search of knowledge is a thing painful, and the painfulness of knowledge is that which maketh the will so hardly inclinable thereto.'