Repent.

Acts 2:35–40 KJV 1900

35 Until I make thy foes thy footstool. 36 Therefore let all the house of Israel know assuredly, that God hath made that same Jesus, whom ye have crucified, both Lord and Christ. 37 Now when they heard this, they were pricked in their heart, and said unto Peter and to the rest of the apostles, Men and brethren, what shall we do? 38 Then Peter said unto them, Repent, and be baptized every one of you in the name of Jesus Christ for the remission of sins, and ye shall receive the gift of the Holy Ghost. 39 For the promise is unto you, and to your children, and to all that are afar off, even as many as the Lord our God shall call. 40 And with many other words did he testify and exhort, saying, Save yourselves from this untoward generation.

2 Chronicles 7:14 KJV 1900

14 If my people, which are called by my name, shall humble themselves, and pray, and seek my face, and turn from their wicked ways; then will I hear from heaven, and will forgive their sin, and will heal their land.

Hebrews 6:1–3 KJV 1900

1 Therefore leaving the principles of the doctrine of Christ, let us go on unto perfection; not laying again the foundation of repentance from dead works, and of faith toward God, 2 Of the doctrine of baptisms, and of laying on of hands, and of resurrection of the dead, and of eternal judgment. 3 And this will we do, if God permit.