Matthew 5:28 - The Sin Of Lust

Whosoever looketh on a woman to lust after her hath committed
adultery with her already in his heart.
Mat 5:28 (KJV)

Jesus' words specifically condemned lust as a form of adultery.
[New Bible Companion]

Adultery is using another person as a sex object. Lust is
viewing another person as a sex object. Christ wants us to realize that
both the act and attitude are sinful. Righteousness calls for us to
view all human beings as persons of worth and value. We are to serve
others, not use them. [The 365-Day Devotional Commentary]

If voluntary and deliberate looks and desires make adulterers
and adulteresses, how many persons are there whose whole life is one
continued crime! whose eyes being full of adultery, they cannot cease from
sin, <2 Pet. 2:14>. Many would abhor to commit one external act
before the eyes of men, in a temple of stone; and yet they are not
afraid to commit a multitude of such acts in the temple of their
hearts, and in the sight of God! (Adam Clarke Commentary)

It was Jesus' teaching that thoughts are just as important as
deeds, and that it is not enough not to commit a sin; the only thing
that is enough is not to wish to commit it. . . . By the world's
standards a man is a good man, if he never does a forbidden thing. The
world is not concerned to judge his thoughts. By Jesus' standards, a
man is not a good man until he never even desires to do a forbidden
thing. Jesus is intensely concerned with a man's thoughts.  [Barclay
Commentary]

The Old Testament law said that it is wrong for a person to have
sex with someone other than his or her spouse (Exodus 20:14). But
Jesus said that the desire to have sex with someone other than your
spouse is mental adultery and thus sin. Jesus emphasized that if the
act is wrong, then so is the intention. To be faithful to your
spouse with your body but not your mind is to break the trust so vital
to a strong marriage. [Life Application SB]

Gouge it out . . . cut it off (5:29-30) This is hyperbole, a
figure of speech in which exaggeration is used to emphasize a point.
Jesus used hyperbole here to get his listeners' attention: Sin is
deadly serious radical measures are required to eradicate It.
Persistent or recurring sin jeopardizes spiritual life much as a gangrenous
infection threatens physical health. [Quest SB]

When Jesus said to get rid of your hand or your eye, he was
speaking figuratively. He didn't mean literally to gouge out your eye,
because even a blind person can lust. But if that were the only choice,
it would be better to go into heaven with one eye or hand than to
go to hell with two. We sometimes tolerate sins in our lives that,
left unchecked, could eventually destroy us. It is better to
experience the pain of removal (getting rid of a bad habit or something we
treasure, for instance) than to allow the sin to bring judgment and
condemnation. Examine your life for anything that causes you to sin, and take
every necessary action to remove it. [Life Application SB]

He who refuses to see, hear, taste, smell, or touch that which
is suggestive of sin has gone far toward avoiding sinful thoughts.
He who immediately banishes evil thoughts when, momentarily, they
may flash upon his consciousness, thereby avoids the development of
a habitual thought pattern that conditions the mind to commit sin
when the opportunity presents itself. [SDA Commentary]

SEEING IS DOING - Both Jesus and the Old Testament teach that
God's law is concerned not only with external and outward actions but
also with the attitudes of heart and mind that lead to the actions.
The action as well as the intent to carry out the action are both
condemned as violations of God's law. In the seventh commandment Jesus
includes the lustful look and the sinful imagination. There is adultery
of the body and adultery of the mind. Job spoke of making a
covenant with his eyes, and not gazing at a virgin (31:1). Peter also
makes reference to those who have "eyes full of adultery and that
cannot cease from sin" (2 Pet. 2:14). Control of the heart and of the
body begins with control of the eyes. This I say then, Walk in the
Spirit, and ye shall not fulfil the lust of the flesh. Gal 5:16 (KJV)
[Daily Devotional Bible mod]

APPLICATION: How are you fulfilling Jesus' command to be perfect
before God? Do you fall short by lusting, lying, cheating, coveting, or
gossiping? When you battle one of these temptations, instead of giving in,
pray, sing a worshipful song, or think of a memorized verse. Praise
God instead of giving in. [Inspirational SB mod]

It will require a sacrifice to give yourself to God; but it is a
sacrifice of the lower for the higher, the earthly for the spiritual, the
perishable for the eternal. God does not design that our will should be
destroyed, for it is only through its exercise that we can accomplish what
He would have us do. Our will is to be yielded to Him, that we may
receive it again, purified and refined, and so linked in sympathy with
the Divine that He can pour through us the tides of His love and
power. MB60-63