I just want to share a very interesting note written on Mark 3:13 (the calling of the 12 apostles of Christ), from the Life Application Study Bible. Here it is (verbatim):
What does it mean to hear the “call” of God?
First, God calls you to faith in Jesus. You will know this call by the growing desire in your heart to settle the matter of peace with God speedily. Respond to him–answer with a grateful, “Yes, Lord, I need you!”
Second, God calls you to service in Jesus’ name. Wherever you are (and sometimes you need to move), whatever you’re doing (and sometimes you need to upgrade your skills), God has a place of service for you. Jesus calls you and he wants you. Answer this call thoughtfully, seriously, in consultation with other Christians, saying, “Yes, Lord, I love you and will follow you!”
Remember these 2 essential responses, and I am sure, God would bestow his grace and blessing continually and abundantly, with unspeakable joy, everlasting.
Soli Deo Gloria