To you, O Lord, I call; my rock, be not deaf to me, lest, if you be silent to me, I become like those who go down to the pit. -Psalm 28:1 (ESV)
David supplicates the Lord to hear his prayer. To be like those who go down to the pit (to Sheol) is to not have an audience with the Almighty. The Lord is deaf to their pleas and silence is his response to their petitions. But this is not the case with God’s elect. He hears the prayers of those who are in Christ. This is one way John encourages believers in the apostolic period. He writes,
“And this is the confidence that we have toward him, that if we ask anything according to his will he hears us.” (1 John 5:14)
It’s also why the author of Hebrews exhorts his audience, similarly.
Hebrews 4:14–16 (ESV): 14 Since then we have a great high priest who has passed through the heavens, Jesus, the Son of God, let us hold fast our confession. 15 For we do not have a high priest who is unable to sympathize with our weaknesses, but one who in every respect has been tempted as we are, yet without sin. 16 Let us then with confidence draw near to the throne of grace, that we may receive mercy and find grace to help in time of need.