Abraham says it to God when he has been called to sacrifice Isaac.
Some time later God tested Abraham. He said to him, "Abraham!" "Here I am," he replied. -Genesis 22:1When Abraham heard God's voice speak his name, he immediately answered the call with "Here I am." He didn't pretend he didn't hear God, he didn't roll his eyes wondering what he would be asked to do, he didn't doubt that he had heard God. He stood (or maybe he fell to his knees in surrender) eager to do whatever special thing God was calling him to do.
In this case, God called Abraham to a test of faith. Would Abraham sacrifice his long-promised son at God's command? Or would he think it a ridiculous request and ignore it? We all know what actually happened. Abraham, in telling God "here I am," agreed to go and do anything for his LORD. I shudder to think what I would do with this specific call. But then again, I am not and never will be commended for my faith as the ancients were (Hebrews 11:2).
Moses says it to God when he is called to lead God's people out of Egypt.
When the LORD saw that he had gone over to look, God called to him from within the bush, "Moses! Moses!" And Moses said, "Here I am." -Exodus 3:4When Moses heard God's voice speak his name, he immediately answered the call with "Here I am." Just like Abraham, Moses had a strong desire to serve his LORD. After He called Moses and found an eager servant, God proceeded to tell Moses his mission:
So now, go. I am sending you to Pharaoh to bring my people the Israelites out of Egypt. -Exodus 3:10Being a man without a soaring self-esteem, Moses' response was one that I can relate to:
But Moses said to God, "Who am I, that I should go to Pharaoh and bring the Israelites out of Egypt?" -Exodus 3:11Suddenly he wasn't so sure about being eager to follow God. But God, being ever loving and always providing, gave Moses all the necessary information he would need for his task, as well as a big dose of support and encouragement. God promises Moses that He will be with him and that he will teach him what to say (Exodus 3:12, 4:12).
But Moses said, "O Lord, please send someone else to do it." -Exodus 4:13
God also promises us that He will be with us in whatever we do, and especially when we are doing whatever His special calling is in our lives.
When God calls you to something specific (or if He is waiting on your response right now), humbly fall before him uttering the words of the ancients:
Then I heard the voice of the Lord saying, "Whom shall I send? And who will go for us?" And I said, "Here am I. Send me!" -Isaiah 6:8When we are called, we should strive to have more of Abraham's response--not blindly following orders, but eagerly surrendering. Though Moses also responded to God's call, the eagerness of his original utterance of "hineini" floundered when he heard the task at hand. When God calls our name AND when he sets a task before us, "hineini" should be the shout from our hearts, and, in turn, our lives.