In today readings we are told the story of the call of three different persons in different times.
The first one is Isaiah on Is 6:1-8. The second one is Peter on Lk 5:1-11 And the third one is Paul on 1 Cor 15:1-11.
 
Isaiah, around the year 739 B.C finds himself in a vision in the presence of Yahweh and his angels. He cries out: "Woe is me, I am doomed! For I am a man of unclean lips, living among a people of unclean lips; yet my eyes have seen the king, the Lord of Hosts." Isaiah recognizes his sinful state in a sinful world. He feels himself unworthy to see God on his throne. His lack of holiness in front of the Most Holy let him feel that he is doomed. Because he recognizes his sins and acknowledge the greatness of God. "One of the seraphim flew to me, Isaiah says, holding an ember that he had taken with tongs from the alter. He touched my mouth with it, and said, "See, now that this has touched your lips, your wickedness is removed, your sin purged". God is the only one who can purify us, can change our lives and can trust us again after we recognize our sins and then he sends us in mission. "Then I heard the voice of the Lord, continues Isaiah, saying, "Whom shall I send? Who will go for us?" And here Isaiah make his commitment to serve God for ever." Here I am, I said; send me."

Peter around the year 30-31A.D. He is just a fisherman, he does not know better. Jesus comes and start first to preach from his boat. Then he asks Peter "to put out into deep water and lower the nets for catch." Peter protests, as a fisherman he knows better "Master, we have worked hard all night and have caught nothing." As if he is telling Jesus, in preaching you are good, but in fishing, I know better than you do. Jesus performs the miracle of the fishing. Peter like prophet Isaiah, recognizes his sins saying: "Depart from me, Lord, for I am a sinful man". Jesus, as Yahweh did to Isaiah, will put his trust on him and call him to the mission: "Do not be afraid, from now on you will be catching men". And like Isaiah, Peter will take a commitment for his life: "When they brought their boats to the shore, they left everything a followed Jesus."

Paul around the year 33-34 A.D. He was a persecutor of the Christians. He knows enough himself that he cannot ask to be called an apostle he says that Jesus appeared to him, as to one born abnormally: "For I am the least of the apostles, not fit to be called an apostle, because I persecuted the church of God." Paul also then recognizes his sinfulness and tells how God put again his trust on him and sent him in mission.
 
Do you see with me the greatness of God. He trusts us again and again.
Perhaps if your recognize humbly and honestly your sinfulness, the Lord will choose you to serve in his mission. You can be the greatest sinner. God can help you to change if you recognize honestly what really you are!
When God calls, you need to make a commitment for all your life.
Listen then, please, to the call of God.