I normally do not expand on a question I set. However, in this instance, I think it is best to provide some information on the part;
وَمَكَرُوا وَمَكَرَ اللَّهُ
The translation of مَكَرَ is found to be "he deceived".
However, one must be very careful here. If we should translate the sentence to "Allah deceived", then we are attributing a characteristic to Allah that He is well above and we seek refuge from such an action.
Thus, you find alternate meanings such as, plan, plot, etc used in translations of the Qur'an.
To clarify further, take the translation;
"They planned/plan (to deceive) and Allah also planned/plans (to meet their deception)"
As mentioned, Allah cannot be deceived, and thus, Allah is aware of their feeble attempts to try and deceive but Allah meets their deception. So, in reality they do not deceive anyone but their own souls as they believe they have deceived their targets, wheras the opposite holds to be true.
There are other instances of such phenomenon in the Qur'an and the same idea applies.
I have attached a lecture delivered in Arabic by منقذ بن محمود السقار addressing such an issue.
http://download.media.islamway.com/lessons/mnqezsaqqar/204_Monqiz_Makr.mp3
For further clarifications, below is an extract from Ibn Kathir;
Allah says;
وَمَكَرُوا وَمَكَرَ اللَّهُ ۖ وَاللَّهُ خَيْرُ الْمَاكِرِينَ
And they plotted, and Allah planned too. And Allah is the Best of those who plot.
Allah states that the Children of Israel tried to kill
`Isa by conspiring to defame him and crucify him.
They complained about him to the king who was a
disbeliever. They claimed that `Isa was a man who
misguided people, discouraged them from obeying the
king, caused division, and separated between man and
his own son. They also said other lies about `Isa, which
they will carry on their necks, including accusing him of
being an illegitimate son.
The king became furious and sent his men to capture
`Isa to torture and crucify him. When they surrounded
`Isa's home and he thought that they would surely
capture him, Allah saved him from them, raising him up
from the house to heaven.
Allah put the image of `Isa on a man who was in the
house; when the unjust people went in the house while it
was still dark, they thought that he was `Isa. They
captured that man, humiliated and crucified him. They
also placed thorns on his head.
However, Allah deceived these people. He saved and
raised His Prophet from them, leaving them in disarray
in the darkness of their transgression, thinking that they
had successfully achieved their goal.
Allah made their hearts hard, and defiant of the truth,
disgracing them in such disgrace that it will remain with
them until the Day of Resurrection. This is why Allah
said,
وَمَكَرُوا وَمَكَرَ اللَّهُ ۖ وَاللَّهُ خَيْرُ الْمَاكِرِينَ
And they plotted, and Allah planned too. And Allah is the Best of those who plot.
والله أعلم