"The Spirit is God's guarantee that he will give us the inheritance he promised and that he has purchased us to be his own people. He did this so we would praise and glorify him." Ephesians 1:14 NLT
subnotes: the Spirit is both God's guarantee of future blessings and a foretaste of eternal life and power. The believers eternal inheritance includes everything he promised (see also 1:18, Romans 8:17, 2 Corinth. 1:22, 5:5, Galat. 3:29, 4:7, Colos. 1:12, 3:24, Titus 3:7)
Greek word study: Guarantee-arrabon (0728)-deposit, pledge. This noun means the deposit or pledge that guarantees the completion of a transaction between two parties. It is used figuratively of the Holy Spirit, whose presence guarantees the promise of eternal life to those who believe the Good News.
purchased-apolutrosis (0629)-redemption. This noun refers to buying the freedom of a slave or captive by paying a ransom. In the NT, it is used figuratively of the results of Christ's work, releasing people from the power of sin and death. see: luke 21:28, rom. 3:24, 8:23, 1 cor 1:30, eph 1:7, 4:30, col 1:14, heb 9:15, 11:35