Ephesians 1:13
And you, too, by your union with him, after you had heard the Message of the Truth, the Good News of your Salvation--you believed in him and were sealed as his by receiving the holy Spirit, which he had promised.
Ephesians 4:30
And do not grieve God's Holy Spirit; for it was through that Spirit that God sealed you as his, against the Day of Redemption.
2 Timothy 2:19
Yet God's firm foundation still stands unmoved, and it bears this inscription-- 'THE LORD KNOWS THOSE WHO ARE HIS'; and this-- 'LET ALL THOSE WHO USE THE NAME OF THE LORD TURN AWAY FROM WICKEDNESS.'
Revelation 7:2
And, in the east, I saw another angel, ascending, holding the seal of the Living God; and he cried in a loud voice to the four angels, to whom there had been given power to harm the earth and the sea--