Evil is before you - i. e. "your intentions are evil." Great as the possible infliction might be, Pharaoh held it to be a less evil than the loss of so large a population.

Let the Lord be so with you - This is an obscure sentence. Some suppose that Pharaoh meant it as a curse, as if he had said, "May your God be as surely with you, as I shall let you go!" For as he purposed not to permit them to go, so he wished them as much of the Divine help as they should have of his permission.

Look - for evil is before you - ראו כי רעה נגד פניכם reu ki raah neged peneychem, See ye that evil is before your faces - if you attempt to go, ye shall meet with the punishment ye deserve. Probably Pharaoh intended to insinuate that they had some sinister designs, and that they wished to go in a body that they might the better accomplish their purpose; but if they had no such designs they would be contented for the males to go, and leave their wives and children behind: for he well knew if the men went and left their families they would infallibly return, but that if he permitted them to take their families with them, they would undoubtedly make their escape; therefore he says, Exodus 10:11, Go now ye that are men, and serve the Lord.

And he said unto them, let the Lord be so with you, as I will let you go, and your little ones,.... Either as mocking them, let the Lord you talk of be with you if he will, and let him deliver you if he can, as I shall let you go with your children, which I never will; or as wishing them ill, that the Lord their God may be with them, as he should dismiss them on their proposal, that is, not at all; he wishes they might never have the presence of the Lord, or receive any from him, till he should dismiss them, which he was determined never to do in the manner they desired; and therefore the sum of his wish or imprecation is, that they might never enjoy any benefits from the Lord; the first sense seems to be best:

look to it, for evil is before you; which is either a charge of sin upon them, that they had an evil design upon him, and intended to raise a mutiny, make an insurrection, and form a rebellion against him; or a threatening to inflict the evil of punishment upon them, if they would not comply with his terms; and it is as if he should say, be it at your peril if you offer to go away in any other manner than it is my pleasure.

And he said unto them, Let {d} the LORD be so with you, as I will let you go, and your little ones: look to it; for {e} evil is before you.

(d) That is, I hope the degree of affection that the Lord has for you is no more than the degree to which I want to let you go.

(e) Punishment is prepared for you. Some read, You intend some mischief.

10:10 Let the Lord be so with you, as I will let you go, and your little ones - He now curses and threatens them, in case they offered to remove their little ones, telling them it was at their peril. Satan doth all he can to hinder those that serve God themselves, from bringing their children in to serve him. He is a sworn enemy to early piety, knowing how destructive it is to the interests of his kingdom.

10:1-11 The plagues of Egypt show the sinfulness of sin. They warn the children of men not to strive with their Maker. Pharaoh had pretended to humble himself; but no account was made of it, for he was not sincere therein. The plague of locusts is threatened. This should be much worse than any of that kind which had ever been known. Pharaoh's attendants persuade him to come to terms with Moses. Hereupon Pharaoh will allow the men to go, falsely pretending that this was all they desired. He swears that they shall not remove their little ones. Satan does all he can to hinder those that serve God themselves, from bringing their children to serve him. He is a sworn enemy to early piety. Whatever would put us from engaging our children in God's service, we have reason to suspect Satan in it. Nor should the young forget that the Lord's counsel is, Remember thy Creator in the days of thy youth; but Satan's counsel is, to keep children in a state of slavery to sin and to the world. Mark that the great foe of man wishes to retain him by the ties of affection, as Pharaoh would have taken hostages from the Israelites for their return, by holding their wives and children in captivity. Satan is willing to share our duty and our service with the Saviour, because the Saviour will not accept those terms.