I am sending you this to ask for an apology and a retraction. You had no right to say what you did to your son, my spouse. If it was true, it was not your place to say it, and certainly not in such an impersonal method as an email. Even if it was true, he is a grown man and it is not your place to tell him when he is doing bad and doing good. His life choices are just that; his choices. If you claim to believe in free will, if you believe in personal moral responsibility, if you believe that "God wants him to make the right choice" then it is your duty to back off and let him make that choice. For himself. It is between no one but himself and God (and me, as his spouse).
But the real issue is that what you said, the accusations you made, were not true. They are not true. You can bluff and bluster, posture and pose all you want, but the things you said were nothing but a bunch of hot air. Your son is not lazy, nor is he a quitter. True, he is not of the same personality as you or I, but not everyone was made to be forceful and strongly opinionated. There is nothing about him that makes him less of a man than you. You are completely and utterly wrong if you think he has to be stubborn as a mule and strong-willed as an ox to be a real man. You have missed the point entirely if you think your sons have to be you to be real, grown adults.
And as to the charge that he is just quitting because it is hard, let me just tell you that you haven't a clue, not a clue what has been going on with our life lately. And do you know why that is? Because we don't tell you. None of your children really let you in on all of the intimate details of your life, because all of them (and their significant others) know the truth about you; you will impose your will on their (and our) lives if you can help it. I don't know if that is what you mean to do, but that is definitely what you have done, and what it appears you are still doing. You can tell me that as their father you are responsible to God, or that you only have their best interests at heart, and I'm sure you really believe that. But the God of the bible does not force people to turn their hearts or to repent or to "do the right thing." The God of the bible waits patiently for repentance, offers up nearly unlimited opportunity to turn and make the right choice, and wants people to turn to the light of their own accord, of their own free will. If you want to believe in a God that is controlling, short-tempered, vengeful, impatient, and full of wrath, that is your prerogative. But you may not impose such a God on your son or on me any more. This ends now.
In case you took that statement to mean something drastic, like we're going to cut you out of our lives forever, please don't. Your son loves you with all of his heart, and I love you too, and we would never wish to end a relationship with family members. But it is because your son loves you that I must insist that you no longer name-call to get your way. You may not ever, ever tell him he is incompetent, lazy, a quitter, weak, or anything else. I forbid you to even imply it. He is my family and I am his. We don't need you to tell us what to do. All we need from you is love, unconditional love, and support. If you can't do this, if you can't resist the urge to control, manipulative, and wound his heart, then I will have to insist that you do not contact him until you can. We will continue to Skype you, but no emails, no letters, no one-on-one phone calls if you cannot behave as a loving, caring, concerned father.
Please do not try to argue with me about this. I don't care if you think I am right or wrong or just off on a few points or a controlling heartless bitch. I am not sending this to ask you a question or debate the finer points of fatherhood. I am sending this to tell you that I will not take this any more. I will not tolerate having to soothe your son's wounded heart every time you drop a heartless word here, or send a mean email there. He deserves better than that email you sent, and I demand it for him.
Your daughter-in-law, with love and hope
Not sure if I should in fact send this to my father-in-law, since I think my spouse might not like it, but I am very upset and seriously considering it. No one deserves to be treated like offal by their parents.