Evangelical shorthand for the gospel is to "ask Jesus into your heart," or "accept Jesus as Lord and Savior," or "give your heart to Jesus." These phrases may not be wrong in themselves, but the Bible never tells us, specifically, to seek salvation in those ways. The biblical summation of a saving response toward Christ is "repentance" and "belief".
He who believes in the Son has everlasting life; and he who does not believe the Son shall not see life, but the wrath of God abides on him (John 3:36 [NKJV])
"Sirs, what must I do to be saved?”...“Believe on the Lord Jesus, and you will be saved—you and your household.” (Acts 16:30-31, HCSB)
To him who does not work but believes on Him who justifies the ungodly, his faith is accounted for righteousness (Rom. 4:5 [NKJV])
If you confess with your mouth the Lord Jesus and believe in your heart that God has raised Him from the dead, you will be saved. 10 For with the heart one believes unto righteousness, and with the mouth confession is made unto salvation (Rom. 10:9-10 [NKJV])
Belief...means acknowledging that God told the truth about Jesus, namely that He is Lord and that He has finished forever the work of salvation...Repentance...means "acting" on that belief. Repentance means reversing your direction based on who you understand Jesus to be. It was the first response Jesus called for in His preaching of the gospel (Mark 1:15), and what Paul said God had commanded all men everywhere to do now that Jesus had been resurrected (Acts 17:30). Apart from repentance there is no salvation.
You can "ask Jesus into your heart" without repenting and believing, and you can repent and believe without articulating a request for Jesus to come into your heart.
Repentance and faith are heart postures you take toward the finished work of Christ.
J.D. Greear, Stop Asking Jesus Into Your Heart