“John answered, ‘A person cannot receive even one thing unless it is given him from heaven.” ESV
Calvinists interpret this verse to support their position that God saves only those whom He has elected. But to come to that conclusion here, you have to already have that position in mind. Whenever you approach God’s Word with preconceived ideas, you will likely only see Scripture through those lens.
But in its context here, John the Baptist isn’t even talking about salvation. He is talking about his call of service, his call to go before Christ to prepare His way. He was saying that this call was not his own doing, but something that God had given to him.
But even if we can expand the definition here to include all things, and we surely can, and should, the idea of a special election of individuals to salvation has to be read into this, and assumed according to that system of belief.
Salvation is from God, and the plan of salvation is from God. No one can receive salvation apart from the grace and plan of God. We cannot receive it unless given to us from heaven. But that does not mean that we are selectively chosen for it. God’s plan of salvation is available to all. Everyone who places their faith in Christ, will obtain forgiveness of sins and eternal life. That’s His plan, that’s what He has given to us. Those who respond to the message of Christ from a willing heart of faith, from a free will (as the Holy Spirit does His work in our hearts), are given eternal life. That’s what God has given to us.