. . . our gospel came to you not only in word, but also in power . . .
-- 1 Thessalonians 1:5
The "but also" is an and, not an or.
The gospel is a word, a message, an item of news about something that happened. It comes in word. It comes as more than word, but certainly not less.
The gospel comes in word and takes hold of some in power, by the grace of God through the power of the Spirit.
The Church historically has fallen for equal and opposite errors in regard to the gospel and its power.
Some know the gospel is word but don’t think it’s power, so we try hard to manipulate people to make decisions. Thus additional verses of "Just As I Am," emotional pleas for raised hands, impulse-tugging scare tactics. We believe someone's decision for Christ hinges on our effectiveness in the invitation.
Some know the gospel is power and so become stingy with the gospel as word, so they abdicate responsibility to share the word. They figure since election is true, God will take care of saving people apart from mission.
Both overreactions are wrong; both ignore Scripture and even disobey it. The gospel comes in word and power. Let’s be faithful in our role and trust God to be faithful in his.