For Christians who feel nervous about sharing their faith, Scott Gentry offers a timely Pentecost reflection on the Spirit’s help, guidance, and power in evangelism.

A while ago, I was outside Marylebone Station with a small group, sharing the gospel with passers-by. One person from our team was speaking, and the rest of us were nearby – watching, praying, and ready to have conversations if people stopped.

As I stood there, my attention was drawn to a young woman sitting on a wall, reading a large book. Something about it caught my eye. Could that actually be a Bible? It seemed unlikely, and at first I dismissed the thought. But the more I tried to ignore it, the more I felt a quiet nudge: Go and ask her if she understands what she’s reading.

I hesitated. It felt awkward, and I wasn’t sure how it would land. But after a moment, I went over and asked.

She told me she had recently bought a Bible and started reading from the beginning. She was now in Exodus and had a lot of questions. We ended up speaking for quite a while, working through what she was reading and looking at how it pointed to Jesus. Later that same day, we unexpectedly crossed paths again elsewhere in London. It was one of those moments where it became clear this wasn’t random – God was already at work.

Looking back, what stands out is not just the conversation itself, but how it began. I hadn’t planned it, and I certainly didn’t create the opportunity. I simply responded, however imperfectly, to what I believe was the gentle leading of the Holy Spirit.

That experience captures something important about evangelism. Many Christians have a real desire to share their faith, and rightly so. Yet it’s possible to step out with enthusiasm while still relying mainly on our own instincts, confidence, or experience. Pentecost reminds us that from the very beginning, witness flowed not from human initiative alone, but from the Spirit’s power and presence.

So, as we think about sharing the gospel, here are three reasons why we need to go out in the power of the Holy Spirit.

At Webber Street Homeless Day Centre in Waterloo, vulnerability is something I think about often. Every day, we open the Bible with our guests and speak about Jesus Christ, the God who sees us, knows us, and loves us.

Some guests hear the gospel for the first time. Others have heard it every day for years. Time and time again, I’ve noticed that some of the moments where people seem to connect most deeply are the moments when staff are willing to speak honestly about their own struggles, grief, fears, or weakness. There is something deeply disarming about vulnerability.

Mental health struggles are often accompanied by shame. We convince ourselves that sadness, anxiety, grief, or loneliness are things to hide. Even when people ask how we are doing, many of us instinctively minimise what we are carrying. Vulnerability, however, has a way of pulling people out of hiding too.

Perhaps that makes sense, because at the heart of Christianity is already an act of vulnerability. To become a Christian is to admit that we are not self-sufficient. It is acknowledging our need for grace, forgiveness, and a Saviour. Salvation begins with honesty.

This Mental Health Awareness Week, here are a few things I’ve learned about vulnerability through life and ministry at Webber Street.

1. Because the Holy Spirit is our Helper

Jesus never intended His followers to carry out His mission alone. Before sending them out, He made a promise:

“You will receive power when the Holy Spirit comes on you; and you will be my witnesses…” (Acts 1:8)

Evangelism can feel intimidating, even for those who’ve been Christians for many years. There are moments when we’re unsure what to say, how to begin, or whether we should speak at all. That’s precisely why Jesus speaks of the Spirit as our “Advocate” or “Helper” (John 14:26) – the one who comes alongside us.

The language is deeply personal. The Spirit is not simply an abstract force or a vague influence, but God’s own presence with us, actively helping, guiding, and strengthening.

That is often how His help is experienced. It may not be dramatic. It can be as simple as a quiet prompting, a growing sense that we should speak to someone, or the right words coming at the right moment. Thinking back to the earlier story, the key turning point was not confidence or preparation, but recognising and responding to that nudge.

When we remember that the Holy Spirit is our Helper, evangelism begins to look different. Rather than feeling that everything depends on us, we begin to see ourselves as participants in something God is already doing. We’re not initiating every moment from scratch. We’re being led into them.

Practical tip: Before starting a conversation, pause briefly and acknowledge your dependence on the Spirit. Ask for clarity, courage, and attentiveness to His leading.

2. Because the Holy Spirit prepares people before we arrive

One of the greatest pressures in evangelism is the feeling that we must make something happen. We can assume that if we don’t explain everything clearly enough, or respond to every question well, then the opportunity has been wasted.

Scripture points us in a different direction. While we’re called to speak faithfully, only God can bring about real change in someone’s heart.

Jesus makes this clear when He says:

“No one can come to me unless the Father who sent me draws them” (John 6:44)

This means that in every conversation, there may already be a story unfolding that we cannot see. The woman reading her Bible at Marylebone was not starting from zero. God had already been at work in her life before I ever spoke to her.

At the same time, the Bible doesn’t minimise the reality of resistance. People don’t always respond because they prefer to remain in the dark rather than come into the light (John 3:19), and there’s also a spiritual blindness at work (2 Corinthians 4:4). Evangelism, then, is never just about exchanging ideas. It’s a spiritual work that requires spiritual dependence.

This is why prayer is not an optional extra. It’s central. When we pray, we’re asking God to do what we can’t – to open eyes, soften hearts, and bring understanding.

Understanding this reshapes our expectations. Our role isn’t to produce a result, but to be faithful, attentive, and dependent. God’s role is to transform.

Practical tip: Pray for the people you hope to speak with, asking God to show you where He’s already at work. Let that shape how you approach the conversation.

3. Because evangelism requires ongoing dependence, not a one-off moment

It’s possible to think of the Holy Spirit’s work mainly in terms of big moments – times of boldness, clarity, or unusual opportunity. Yet the New Testament consistently describes a pattern of ongoing dependence.

Paul’s instruction to “be filled with the Spirit” (Ephesians 5:18) carries the sense of something continuous. It’s not a one-time experience, but a way of life.

That’s particularly important in evangelism. No two conversations are the same, and we often find ourselves in situations we couldn’t have predicted. We need more than initial enthusiasm or past experience. We need present dependence.

There’s a well-known comment attributed to D. L. Moody. When asked why he needed to be filled with the Spirit so often, he replied, “Because I leak.” It’s a simple observation, but it captures something true about the Christian life. Left to ourselves, we drift.

Scripture describes this drift in relational terms. We’re warned not to grieve or quench the Spirit (Ephesians 4:30; 1 Thessalonians 5:19). In practice, that may look like neglecting holiness, becoming absorbed in the world around us, or failing to honour Jesus in the way we live. In our evangelism, it might look like defaulting to self-reliance, speaking before praying, or ignoring the quiet promptings we’ve been given.

Dependence on the Spirit, by contrast, keeps us attentive and close to Him. It shapes not only what we say, but how we listen, how we respond, and when we choose to speak. It reminds us that effectiveness in evangelism is not about our ability, but about God’s activity.

This ongoing reliance is not restrictive. It’s freeing. We’re no longer trying to control outcomes or carry responsibility that doesn’t belong to us. Instead, we take each moment as it comes, trusting the Spirit to lead and to work.

Practical tip: Build the habit of short, quiet prayers before and even during conversations, asking the Spirit to guide your words and your responses in real time.

The story at Marylebone is a simple one, but it points to a deeper truth. Evangelism is not first about creating opportunities, but about recognising and responding to what God is already doing.

Enthusiasm to share the gospel is a good and necessary thing. Yet it was never meant to stand on its own. From Pentecost onwards, the Church’s witness has always depended on the power and presence of the Holy Spirit.

He’s the one who helps us speak, prepares the hearts of those we meet, and sustains us in ongoing dependence.

So, as we step out to share the good news – in planned conversations or unexpected encounters – let us do so with confidence, not in ourselves, but in Him.