Overall meaning : Allah Almighty informs us here that it is the same whether or not the unbelievers are warned, they will not believe in the truth which Muhammad, may Allah bless him and grant him peace, has brought them. That is because Allah has set a seal on their hearts and so guidance will not avail them in the least and has placed a veil on their hearts and sight so much so that they cannot perceive what is bound to guide them. Such unbelievers will surely be doomed to Hellfire as a repayment for their evil deeds.