When I read Joshua 5 this morning, it struck me how God is able to both fill men with His Spirit, and yet also to deplete their spirits. Before Joshua and the Israelites had even crossed the Jordan river, in Joshua 2 Rahab informed the spies that the locals believed "the Lord had given [the Israelites] the land" and "terror has fallen" on its citizens. When the Israelites reached the Jordan, they didn't just swim across: God shut down the river and made it dry while His people crossed, then turned the water back on again once they had reached the other side. Upon hearing this, the kings' "hearts melted, and there was no spirit in them any longer". These leaders of nations who commanded vast armies felt a chill down their spines and the strength leave their limbs when they realized that the true and living God was on the side of their enemies.
And yet in the book of Acts, we see common fishermen who had received no formal religious instruction suddenly stand up, full of God's Holy Spirit, and address the religious leaders at the very top of Judaism with boldness and authority, leading to this remarkable verse: "Now as [the rulers and elders and scribes] observed the confidence of Peter and John and understood that they were uneducated and untrained men, they were amazed, and began to recognize them as having been with Jesus." (Acts 4:13 NASB) These religious leaders were held as the highest authority of the faith, and here were two "uneducated" commoners presuming to teach them scripture.
Why are we so afraid to approach our family, friends, neighbors, and colleagues with God's truth? Jesus tells us, "... do not worry about how or what you are to say; for what you are to say will be given you in that hour. For it is not you who are speaking, but it is the Spirit of your Father who is speaking in you." (Matt 10:19-20 NASB) God loves the people in your life more than you ever will, and He wants them to be saved more than you're capable of wanting. Will He not keep His promise to put just the right words into your mouth? When the moment comes, His Holy Spirit will give you exactly what you need to say. And on top of that, He is in control of your friends' spirits, too! He will adjust their heart to be receptive, opening their eyes to see the truth of the message He has delivered through you. Don't hesitate: when you see the opportunity, share whatever God has placed on your heart, and He will faithfully work in both of you to His good purposes.