Please enjoy this wonderful quote by John Calvin regarding God’s promises to covenant children…
“The third and fourth heads I do not touch. Towards the end of the fifth head they affirm that no transference to a state of grace takes place without Baptism, or a wish for it. Would it not have been better to say, that by the word and sacraments Christ is communicated, or, if they prefer so to speak, applied to us, than to make mention of baptism alone? But they have been pleased to exclude infants from the kingdom of God, who have been snatched away before they could be offered for baptism. As if nothing were meant when it is said that the children of believers are born holy. ( 1 Corinthians 7:14.) Nay, on what ground do we admit them to baptism unless that they are the heirs of promise? For did not the promise of life apply to them it would be a profanation of baptism to give it to them. But if God has adopted them into his kingdom, how great injustice is done to his promise, as if it were not of itself sufficient for their salvation! A contrary opinion, I admit, has prevailed, but it is unjust to bury the truth of God under any human error, however ancient. The salvation of infants is included in the promise in which God declares to believers that he will be a God to them and to their seed. In this way he declared, that those deriving descent from Abraham were born to him. ( Genesis 17:7) In virtue of this promise they are admitted to baptism, because they are considered members of the Church. Their salvation, therefore, has not its commencement in baptism, but being already founded on the word, is sealed by baptism.”
Calvin, John (2013-06-06). Antidote to the Council of Trent on Justification (Kindle Location 42). Fig. Kindle Edition.