Jamieson, Fausset and Brown on Ezekiel 18:14-18

14-18. The third case: a son who walks not in the steps of an unrighteous father, but in the ways of God; for example, Josiah, the pious son of guilty Amon; Hezekiah, of Ahaz (2Ki 16:1-20; 18:1-37; 21:1-22:20).

seeth ... and considereth--The same Hebrew stands for both verbs, "seeth ... yea, seeth." The repetition implies the attentive observation needed, in order that the son may not be led astray by his father's bad example; as sons generally are blind to parents sins, and even imitate them as if they were virtues.