If a man wants to work, he first needs to raise his head: referring to the process of writing the word 夫.
He needs to do so in order to be a fully grown man. 夫 = man.
Only a man who possesses his own family, is a real man. 丈 ＝ husband
One, capable of carrying out a big task. 大 ＝ great things
wow…haha…