'Look' in the Bible

As it is written:Look! I am putting a stone in Zion to stumble overand a rock to trip over,yet the one who believes on Himwill not be put to shame.

One who eats must not look down on one who does not eat, and one who does not eat must not criticize one who does, because God has accepted him.

But you, why do you criticize your brother? Or you, why do you look down on your brother? For we will all stand before the tribunal of God.