God also bearing them witness, both with signs and wonders

Hebrews 2:3-4
King James Version (KJV)

3 How shall we escape, if we neglect so great salvation; which at the first began to be spoken by the Lord, and was confirmed unto us by them that heard Him;

4 God also bearing them witness, both with signs and wonders, and with divers miracles, and gifts of the Holy Ghost, according to his own will?

Acts 14:3
New King James Version (NKJV)

3 Therefore they stayed there a long time, speaking boldly in the Lord, who was bearing witness to the word of His grace, granting signs and wonders to be done by their hands.

Mark 16:20
New King James Version (NKJV)

20 And they went out and preached everywhere, the Lord working with them and confirming the word through the accompanying signs. Amen.

Hebrews 2:4

New King James Version (NKJV)
God also bearing witness both with signs and wonders, with various miracles, and gifts of the Holy Spirit, according to His own will?

New International Version
God also testified to it by signs, wonders and various miracles, and by gifts of the Holy Spirit distributed according to his will.

New Living Translation
And God confirmed the message by giving signs and wonders and various miracles and gifts of the Holy Spirit whenever he chose.

English Standard Version
while God also bore witness by signs and wonders and various miracles and by gifts of the Holy Spirit distributed according to his will.

New American Standard Bible
God also testifying with them, both by signs and wonders and by various miracles and by gifts of the Holy Spirit according to His own will.

King James Bible
God also bearing them witness, both with signs and wonders, and with divers miracles, and gifts of the Holy Ghost, according to his own will?

Romans 1:16
New King James Version (NKJV)

The Just Live by Faith

16 For I am not ashamed of the gospel of Christ, for it is the power of God to salvation for everyone who believes, for the Jew first and also for the Greek.
17 For in it the righteousness of God is revealed from faith to faith; as it is written, “The just shall live by faith.”

“power” in greek = miracles, signs and wonders = Dunamis