Question

Hello Rabbi Michael,
I have an argument with several friends. I claim that it is definitely possible to postpone the issue of bringing children into the world at the beginning of a marriage—that is, to get married at a certain age and decide that it still isn’t possible to have children because of a desire to strengthen the marital relationship first, or alternatively to establish stable financial footing.
My friends disagree with me and argue that according to Jewish law it isn’t possible to act that way, and that the situation is a bit more complicated.
What is the Jewish law in such a case?