Overall meaning :
Allah Almighty states that many among the Bedouins (desert Arabs) came with excuses to the Messenger of Allah, may Allah bless him and grant him peace, to grant them exemption from going into battle, and the hypocrites, who falsely claimed they believed in Allah and His Messenger, remained at home and did not bother to go to him with their excuses. He declares that the unbelievers among the Bedouins will suffer an agonising punishment.
Allah Almighty then mentions the legitimate excuses for not going to war for Allah’s cause, saying: Neither the weak, nor the sick, nor those who do not find the means with which to equip themselves for the battle are considered sinners for failing to go into battle as long as they are true to Allah and His Messenger and behave themselves faithfully towards them. There is no cause of blame or punishment whatsoever against those who do good, and Allah is All-Forgiving, All-Merciful. Nor is blame attached to those who, when they came to you, Muhammad, requesting you to arrange transport for them to fight the battle with you and you said you could find none to carry them, went away in tears, grieving that they could not find anything to spend to prepare themselves for the campaign.
Allah, Exalted be He, then explains the rulings on those who make false excuses, saying: Those who truly deserve punishment are the hypocrites who ask you to exempt them from taking part in the battle even though they are wealthy. They are content to stay at home with women, who are exempt from fighting. Allah has set a seal on their hearts, leaving them bereft of understanding the dire consequences of their actions.