When someone is trying to get our attention, we can respond in a myriad of different ways. We can choose to ignore the call, we can have them leave a message, or we can immediately answer and engage. When God calls us for His purposes, He desires that we immediately respond and continue to journey with him by faith. God is the one who does the work, but faith is what is required of us. If we have faith the size of mustard seed that will be enough, but without faith it is impossible to please God. So, how does trusting God really operate? What must a believer to trust in order for God to fulfill the calling in his life. Exodus 4 teaches us how to respond to God when He calls us into service.