As a believer, you can be sure without a shadow of a doubt that you are saved. You can and should rejoice at the second coming of Christ without being afraid. The word of God sets the records straight in Isaiah 32:17.

The effect of righteousness is peace, quietness, and assurance forever. When you receive the gift of righteousness in Christ you are assured you are His forever. 1 John 5:13

There is no salvation devoid of assurance. God wants you to know that you are saved. He has designed that you receive eternal life before you step into eternity.

Salvation is by grace alone, in Christ alone, through faith alone, for the glory of God alone.

Jesus did the following to assure you of salvation:
1. He prayed about it. John 17:11
2. He preached about it. John 6:38
3. He swore about it. Heb 6:13-20

Eph 1:13 makes us understand that we have been sealed with the Holy Spirit of promise and He has promised to uphold us till the very end.

Be assured in the finished works of Christ.