Long time therefore they tarried there speaking boldly in the Lord, who bare witness unto the word of his grace, granting signs and wonders to be done by their hands.

So Paul and Barnabas spent considerable time there, speaking boldly for the Lord, who affirmed the message of His grace by enabling them to perform signs and wonders.

long time, indeed, therefore, did they abide speaking boldly in the Lord, who is testifying to the word of His grace, and granting signs and wonders to come to pass through their hands.

They stayed therefore a good while, speaking boldly, [confiding] in the Lord, who gave witness to the word of his grace, giving signs and wonders to be done by their hands.