On the Decisive Day, the Day When the two Forces Encountered Each Other

What times they were when the Leader of Both Worlds  battled
his old enemy. They continuously persecuted him until finally he was
compelled to migrate to Madīna.
The enemy was not content with forcing the Noble Prophet 
to leave his beloved and familiar homeland, and set off from Makka with
an army of 1,000 soldiers to attack Madīna. In the battlefield of Badr, the
two armies met. On the other hand only a small group of Muslims had
travelled, which was not an army; they had no weapons, no animals to ride,
no proper means, nothing of significance at all. A few of them had sticks,
some others had arrows, but the majority had nothing:
Those who had two horses, six armours and eight swords, came to
change the fate of the world.
So it was that an army without weapons stood on the one side, whilst
those that were thirsty for bloodshed stood in opposition, a mighty army
prepared with all types of weapons. However, even at that time the Prophet
 was very calm and content. The following incident exemplifies
this:
The Noble Prophet  is drawing the battle lines (at Badr). The
enemy has drawn its lines and is preparing to begin the attack on the
Muslims. However he is still drawing the battle lines and assessing the
position of his men and considering their standing positions. The Prophet
 is carrying out this assessment, and with the help of an arrow in
his hand he is ensuring the lines are absolutely straight. Just like one would
use something straight to make sure a line is straight and not slanted, the
Prophet  used his arrow to organise the ranks of his Companions
and made sure everyone was standing straight in the lines.

While this was happening, a Companion groaned loudly, so the Prophet
 stopped to ask him what had happened. The man replied, “O
Prophet of Allāh! You have scratched me.” Just ponder over this incident;
on the one hand the Muslim army has no weapons, and they are prepared
for fierce combat against a mighty force. Yet there is such a high level of
inner peace and tranquillity that the Companion is informing the Prophet
 that he has been scratched. He continues, “The arrow that you
were using to organise the ranks scratched me.” The Prophet 
sought his forgiveness but the Companion stated, “I will not forgive you
in this manner.”
A similar story which is related and attributed to the time of the
Prophet’s  illness prior to his leaving this world, in which the
Prophet  announced in the Masjid Nabawī, “Those whom I have
wronged can avenge themselves.” A Companion whose name is given as
ʿUkāsha  stood up and commented, “O Messenger of Allāh! Once I was
scratched by you.” Regarding ʿUkāsha’s  story, Ibn al-Jawzī  is of the
opinion that this incident is not related to ʿUkāsha  in Masjid Nabawī
in Madīna, but it is related to Badr just before the battle commenced, the
story which has just been referred to above.
So the Noble Prophet  was straightening the lines, and upon
reaching Sawād ibn Ghaziyya , this Companion suddenly complained
he had been scratched. The Noble Prophet  sought his forgiveness
but he refused and stated, “O Messenger of Allāh! I will not forgive you just
like that; I will take my revenge.” The Noble Prophet  handed him
the arrow and told him to take his revenge. He replied, “Not like this. While
you were straightening the rows, I was scratched on my bare back as I had
no cloth on it, so therefore it is only fair that you also remove your top.”
The Prophet  removed his blessed cloth and stated, “Now avenge
yourself.” He approached the Noble Prophet , embraced him and
kissed the Seal of Prophethood on the Noble Prophet’s  back.
That the Prophet  was unconcerned about all (war-related)
responsibilities and engaged in pleasing the Companion illustrates clearly
the amount of tranquillity experienced by both the Companion as well as
the Prophet  on the decisive day of the Battle of Badr.

Thereafter the battle began, and within a short space of time it came
to a conclusion. An analysis of this battle reveals that there was a distinct
imbalance between the two armies in terms of numbers, preparation,
weapons and material goods. The Companions did not even possess
sufficient and proper clothing, and their hands were empty and feet bare.
This was normal for the Prophet  and the Companions, in fact it is
how they were used to living. Similarly, this is what our elders learned from
the teachings of the Prophet  and implemented in their lives.