I John 4:13 And God has given us his Spirit as proof that we live in him and he is us.
I don't know about you, but there have been times in which I have wondered if it could all be true. I stop and think about what I know to be true in the world around me and what I believe to be true of what I cannot see. In moments of weakness or times of trouble I have wondered if I might be basing my life on what I want to believe instead of what is for real. It is during those times of doubting that I discover just how true it all is. The Spirit of God speaks to me and reassures me that I do not believe in vain. It might be through the Word of God, the beauty and mystery of creation, something I hear, or just the peace I sense in my soul because of forgiven sin.
I know that God is in me and I am in God because the Spirit of God does for me and through me what no one or anything else ever could. There is a mystery to how He works, but it is undeniable that He does. I marvel at the way God confirms His life in me. I marvel at the changes He has made and continues to make in me. I marvel at how He continues to draw me to Him and keeps me from self-destructing.
God has given His Spirit to all who accept Jesus as their Savior to give them confidence that they are indeed children of God. He has given us the Spirit to help us make Jesus Lord of our lives. He has given us the Spirit to empower us to live for Christ now and lead us home to heaven when we die.
There is never a moment in which the Spirit of God is not with us when we live in Christ.