My dear Stephen: where is the money to come from? It is easy enough for you and the other children to live on my income as long as we are in the same house; but I can't keep four families in four separate houses. You know how poor my father is: he has barely seven thousand a year now; and really, if he were not the Earl of Stevenage, he would have to give up society. He can do nothing for us. He says, naturally enough, that it is absurd that he should be asked to provide for the children of a man who is rolling in money. You see, Stephen, your father must be fabulously wealthy, because there is always a war going on somewhere. (1.39)
The play starts out with Lady Brit bringing Stephen into the know about her/their financial problems. You see, because her daughters are getting ready to be married to men who aren't likely to provide well for them (at least at first), she's scrambling to figure out how they will make ends meet. Which means that after years of not seeing her husband, she's inviting him to the house to ask him for some extra cash.
LADY BRITOMART: I must get the money somehow. STEPHEN: We cannot take money from him. I had rather go and live in some cheap place like Bedford Square or even Hampstead than take a farthing of his money. (1.71-72)
Despite the fact that Lady Brit has resigned herself to having to ask her "immoral" husband for his blood money to help support the girls and their husbands, Stephen has real problems with it, especially with all the extra information he's gotten from his mother about his father's history and "immorality."
STEPHEN [bitterly]: We are utterly dependent on him and his cannons, then? LADY BRITOMART: Certainly not: the money is settled. But he provided it. So you see it is not a question of taking money from him or not: it is simply a question of how much. I don't want any more for myself. (1.76-77)
Stephen is trying really hard to take a stand on accepting his father's money, but Lady B is really making it hard for him. Here, she has just informed him that their current lifestyle has been entirely supported by a flat sum of money that Undershaft had already provided, so now the question is not whether his money will help them out, but how much.
LOMAX [leniently]: Well, the more destructive war becomes, the sooner it will be abolished, eh? UNDERSHAFT: Not at all. The more destructive war becomes the more fascinating we find it. No, Mr Lomax, I am obliged to you for making the usual excuse for my trade; but I am not ashamed of it. I am not one of those men who keep their morals and their business in watertight compartments. All the spare money my trade rivals spend on hospitals, cathedrals and other receptacles for conscience money, I devote to experiments and researches in improved methods of destroying life and property. I have always done so; and I always shall. Therefore your Christmas card moralities of peace on earth and goodwill among men are of no use to me. Your Christianity, which enjoins you to resist not evil, and to turn the other cheek, would make me a bankrupt. My morality—my religion—must have a place for cannons and torpedoes in it. (1.212-213)
Just as he refuses to be ashamed of his profession, Andrew Undershaft is not going to be bashful about being rich—and loving it. In his eyes, being rich is a good thing in and of itself, and poverty is an evil that is to be avoided if one can.
UNDERSHAFT: The two things are— CUSINS: Baptism and— UNDERSHAFT: No. Money and gunpowder. (2.227-229)
When explaining the two things necessary to salvation, Undershaft identifies the importance of money. In Andrew's view, along with weapons, money allows for all the good things in life (including virtues) that Dolly and the others care about.
What am I to do? I can't starve. Them Salvation lasses is dear good girls; but the better you are, the worse they likes to think you were before they rescued you. Why shouldn't they av a bit o credit, poor loves? They're worn to rags by their work. And where would they get the money to rescue us if we was to let on we're no worse than other people? You know what ladies and gentlemen are. (2.17)
This is Rummy talking to Snobby Price. Basically, in her view, she is not only getting what she needs by lying to the Army about how bad she/her circumstances are, but she's helping them get donations by giving them a better story about how their converts were transformed. The worse the converts start out, the more the Salvation Army can claim that they've helped people. Sounds, er, totally legit . . . right?
My religion? Well, my dear, I am a Millionaire. That is my religion. (2.164)
As you can probably tell by the overlap in the topics of religion, money, and morality, Undershaft doesn't really distinguish between those categories; his morality is based on an appreciation of money and power, which has essentially become his religion.
Poverty, my friend, is not a thing to be proud of. (2.167)
Given that Andrew Undershaft's religion is being a millionaire, you probably won't be surprised to hear that he thinks that poverty is an awful thing.
I think, my friend, that if you wish to know, as the long days go, that to live is happy, you must first acquire money enough for a decent life, and power enough to be your own master. (2.247)
Here, Andrew and Dolly have been sparring with their respective philosophies of life and happiness. Once again, Andrew reiterates that money is basically the building block of all that's good, in his mind at least.
Yes, money and gunpowder; freedom and power; command of life and command of death. (2.273)
Reiterating the central "pillars" of salvation, Andrew emphasizes the power of money (and gunpowder) over basically everything else—in fact, they have life or death consequences.