Halal and Tayyib foods improve healthy bodies whereas the opposite with Haram products. Haram or mashbuh (suspicious) foods have adverse effects on the physiology of the body.
The body fed by harams is like a building composed of unsound concrete. Just as such buildings tend to be damaged in the slightest blow and to collapse in earthquakes, the body fed by the haram is doomed to collapse both physically and spiritually. Food is a yeast. If the yeast is of good quality, the product will be good, while bad yeast will spoil the raw material.
Besides their physical effects, foods have spiritual effects. Spiritual diseases are the consequences of Harams. Such results spoil the person who tends to Haram, and then the societies. Prohibited acts such as bribery, adultery, interest, liquor, cheating spread like an epidemic over time and the order collapses.
Spiritual diseases such as, gossip, greed, hasad, riya’ are the crops of the bodies that are used to Harams. The harams might be appealing to the soul and perhaps it is easier or economical to supply what is forbidden. Even Harams can be very abundant and widespread. However, this should not lead us to take the easy way out and we should always seek Halal. Of course, the person who will account for Allah from all blessings (nimah)must pay attention to Halal and Haram.
As a matter of fact, Allah (CC) says:
“Say, “Not equal are the evil and the good, although the abundance of evil might impress you.” So fear Allah, O you of understanding, that you may be successful.” (Al-Ma’idah, 100)
The morsel is seed, and thoughts are its fruit. The Halal morsel leads us to altruism (thinking the benefits of others), contemplation (tafakkur) and service. On the other hand, Haram and the mashbuh incline the person to selfishness, ambition, heedlessness and greed.
Maulana Jalaluddin expresses the same sensitivity as follows:
Wean the babe, your soul, from the Devil’s milk,
and after that make it consort with the Angel.
While you are dark and vexed and gloomy,
know that you are sucking from the same breast as the accursed Devil.
The mouthful that gave increase of light and perfection
is obtained from lawful earnings.
The oil that comes and quenches our lamp—
when it quenches a lamp, call it water.
From the lawful morsel are born knowledge and wisdom;
from the lawful morsel come love and tenderness.
When from a morsel you see envy and guile,
ignorance and heedlessness are born, know that it is unlawful.
Will you sow wheat and will it produce barley?
Have you seen a mare bring forth an ass’s colt?
The morsel is seed, and thoughts are its fruit;
the morsel is the sea, and thoughts are its pearls.
From the lawful morsel in the mouth is born
the inclination to serve and the resolve to go to yonder world. (Masnavi, volume 1, p. 106, couples 1640-1648)
When epidemics, previously unknown troubles, earthquakes and similar troubles increase, Halal morsel should be the concern of all because the way of salvation starts with Halal morsel.