Assured of What?
Christ's resurrection is past, but it assures us of the two resurrections yet to come. The first resurrection is reserved for believers, and is unto glory and blessing (1 Thessalonians 4:13-17; Revelation 20:5,6). The second resurrection is for unbelievers, and leads only to judgment (Revelation 20:11-15).
The Believer's Assurance of Life
"If the Spirit of Him that raised up Jesus from the dead dwell in you, He that raised up Christ from the dead shall also quicken your mortal bodies by His Spirit that dwelleth in you" (Romans 8:11).
The Unbeliever's Assurance of Doom
"He hath appointed a day, in the which He will judge the world in righteousness by that man whom He hath ordained; whereof He hath given assurance unto all men, in that He hath raised Him from the dead" (Acts 17:31). "It is appointed unto men once to die, but after this the judgment" (Hebrews 9:27).
Of what are you assured?