"When a temptation comes from without, it is unto the soul an indifferent thing, neither good nor evil, unless consented to. But the very proposal from within, it being the soul's own act, is its sin" (Owen, Indwelling Sin, VI.)
Sin only comes through 5 steps (Feinberg)
*desire for something
*intention to have that object
*plan to get that object
*willingness to have that object, to put plan into action
*movement toward and acquisition of object
Being that Jesus was the God-man (Hypostatic Union, communicatio idomatum), He probably did not go beyond step one.
Temptations of Christ were without sin in their source, nature and result.
Lust is an indwelling sin...maybe triggered by the eyes, and a perceived need/want, but nonetheless, it originates within- and Christ did not inwardly desire any evil thing ("impeccability" and "immutability")
Theology for Today, by Elmer Towns