Master - This is the first time that the word here translated “Master” occurs in the New Testament, and it is used only by Luke. The other evangelists call him Rabbi, or Lord. The word here used means a “prefect,” or one placed “over” others, and hence, it comes to mean “teacher” or “guide.”
At thy word - At thy command. Though it seemed so improbable that they would take anything after having in vain toiled all night, yet he was willing to trust the word of Jesus and make the trial. This was a remarkable instance of “faith.” Peter, as it appears, knew little then of Jesus. He was not then a chosen apostle. Jesus came to these fishermen almost a stranger and unknown, and yet at his command Peter resolved to make another trial, and go once more out into the deep. Oh, if all would as readily obey him, all would be in like manner blessed. If sinners would thus obey him, they would find all his promises sure. He never disappoints. He asks only that we have “confidence” in him, and he will give to us every needful blessing.