This contrast is most clearly seen in their speeches concerning Paris' request to marry Juliet. When Paris first asks, Capulet responds
My child is yet a stranger in the world,
She hath not seen the change of fourteen years;
Let two more summers wither in their pride(10)
Ere we may think her ripe to be a bride.
So he tells Paris to wait a bit, until Juliet is two years older. When Paris tells him that young girls make happy mothers, he's foreshadowing the argument that Lady Capulet will make later. Capulet does not budge, however. He retorts that women essentially lose their childhoods and happiness if they become mothers too early, by saying "And too soon marr'd are those so early made."
Lady Capulet is excited by Juliet's possible marriage. She encourages juliet to marry, essentially before it's too late.
Younger than you,
Here in Verona, ladies of esteem,
Are made already mothers. By my count,(75)
I was your mother much upon these years
That you are now a maid.
At the beginning of the play, Lady Capulet is anxious for Juliet to marry. She remarks that at Juliet's age, she was already a mother. This was the custom of the time period. The Capulets are a wealthy family, and it is of utmost importance to Lady Capulet that her daughter get married before she is considered to be an "old maid". People during this time didn't have long life spans as they do today, and it was thought that a young lady should marry and have children as soon as she entered puberty.
Lord Capulet is not as anxious for his daughter to get married right away at the beginning of the play. He tells his wife that Juliet still has time and should look at possible suitors to see which one she likes. He doesn't believe she should be too hasty in choosing a mate. Lord Capulet's attitude greatly changes later in the play when he orders Juliet to marry Paris.
Juliet's mother ( Lady Capulet ) believes that Juliet should marry young , especially since Juliet's mother was Juliet's age when she had her .
Lord Capulet though , thinks that Juliet is too young to marry , and that there is still time . He believes that she should still take time and look through possible suitors .