Explaination on who a believer is. What his realities are. How that he has been indwelt by the Holy spirit forever.

Explaining clearly how Christ Sacrifice once for all has obtained an external redemption for all. We (believers) now have life eternal. Glory!!!

Our response towards our realities in Christ is Rejoicing. We rejoice evermore. Glory to God

Salvation is a gift from God. It's by grace through faith in Christ Jesus. Once saved is forever saved.

Drawing from the wells of salvation is actually the believers response to the work of salvation. This would have him or her rejoice.