Charles Ellicott Commentary Luke 11:36

"If therefore thy whole body be full of light, having no part dark, it shall be wholly full of light, as when the lamp with its bright shining doth give thee light." — Luke 11:36 (ASV)

If thy whole body therefore be full of light.—The statement reads at first like an identical proposition. "If your whole body is full of light, it will be full of light all over." The apparent truism is, however, the most expressive utterance of a truth.

If the "whole body"—life in all its various manifestations—is illumined by the divine light; if the character is in its measure perfect, as that of the Father is perfect, who is Light, and in whom is no darkness at all (1 John 1:5); if passion, prejudice, ignorance are no longer there—then that character is..."

We expect to hear something else as a climax of praise, but there is no higher word possible; the whole character is "full of light," illumined, flooded by the eternal Light.