in the power of signs and wonders

Romans 15:18-20 . 18 For I will not presume to speak of anything except what Christ has accomplished through me, resulting in the obedience of the Gentiles by word and deed, 19 in the power of signs and wonders, in the power of the Spirit; so that from Jerusalem and round about as far as Illyricum I have fully preached the gospel of Christ. 20 And thus I aspired to preach the gospel, not where Christ was already named, so that I would not build on another man’s foundation;