The magic of God
The narrator refers to his childhood and the close bond he had with his two older brothers as being the magic of God. In their blissful yet cruel innocence, they were the magic of God. They were blissful because of the lack of self-awareness, but cruel in their blunt honesty.
A bomb
Seeing a pregnant lady, the three boys ask her if she’s got a bomb in her stomach. This comes from childhood absorption and mimicking, after hearing their mother refer to her pregnancy as a ticking bomb.
A fistful of seed that God tossed
The narrator’s older brother Manny is the one who is the most violent and aggressive. He also is the most depressed and has the most self-doubts. In one of their conversations he reveals to his younger brother that he thinks that they all are a fistful of seed that God tossed into the mud.
Each little ripple as a life
Recounting one of their trips to Niagara Falls, the narrator talks about a moment when his father held him above the water and jokingly threatened to let him go, saying that he would die if he did so. He remembers wanting his father to let him go, seeing each ripple as a life of its own that began high away in the mountain.