Castillejo was a voluminous writer of verse. His poems are worthy of note, not only on account of their intrinsic merit, but also as being the last manifestation of importance of the older Spanish School of poetry against the younger section under the leadership of Garcilaso de la Vega. That fine melodist and brilliant rhetorician, the Ronsard of Spain, seconded by Boscan and Hurtado de Mendoza, had introduced into his own land the rhythms and cadences employed in Italy; through him the sonnet, the canzone, the octaves of the comic epics, and even the terza rima of the comedy itself had been transplanted into Spanish soil; and he and his followers had created a vocabulary of picked and exquisite terms which, passing through the hands of the magniloquent Herrera, was to end in the monstrous dialect of Gongora and his disciples. Against this revolution Castillejo set his face, fighting gallantly and unavailingly in defence of the antique metrical forms and structures. The use of these he never abandoned, save on one or two occasions when, for purposes of parody, he produced sonnets and octaves. In the poetry of Castillejo, which is written chiefly in “quintillas” and “copias de pié quebrado,” are all the qualities that make the older verse of Spain such pleasant reading—the graceful simplicity, the artless elegance, the fluency and spontaneity (which sometimes, however, degenerates into garrulity), the keen and homely mother wit, often gross but seldom offensive or cruel. He has, however, other qualities which are peculiar to himself, and which give him a place apart even among the school that may be said to end in him; his society verses are bright with a pleasant gossipy amiability; his satires are quick with a certain cynical sprightliness that makes them still amusing and attractive; while one at least of his poems, the “Dialogue between Himself and his Pen,” overflows with a humorous tenderness that is extremely effective. Writing on anything and everything—“On a Green and Yellow Costume,” “On the Wood Guaiacum,” “On a Friend’s Horse called Tristram,” —he of course produced a cloud of rhymes that are intolerable and to be avoided. Some of his “Villancicos,” “Letras,” and “Motes,” however, are charming in despite of years; a not infrequent note in them reminding the reader somewhat of the quaint graces of Charles of Orleans, with whom in this fondness for elaborate trifles Castillejo may be said to have a certain affinity, though immeasurably his inferior in delicacy of touch and artistic restraint. His principal satires, “The Sermon against Love” and the “Dialogue of the Conditions of Women,” are amusing and witty enough; while his “Galatea,” an imitation of Ovid, must be regarded as one of the sweetest pieces of pastoral poetry in the whole range of Spanish letters, and, with the exception of the exquisite little anacreontic to Love, as the best of Castillejo’s many poems.

The strong anti-clerical feelings of Castillejo, himself an ecclesiastic, have been already remarked. His satires were treated exceedingly ill on this account by the officers of the Inquisition, who did not scruple to excise large portions of them, and to fill up the gaps thus caused with screeds of a contrary tendency, the work of their own hack rhymesters, who had at this period a great deal of work to do of the same sort. The poems themselves are divided into three books, the first devoted to “Love,” and the second to “Conversation and Pastime;” while the third is composed of moral and religious verses. The best text is that given in the BibUoteca de Autores Españoles, vol. xxxii., Madrid, 1832.