Is the sinner's prayer unbiblical as some claim ? my answer is it is biblical. First let me share Biblical examples. II Chronicles 7:14, Psalm 51(one of the psalms of David), the prodigal son, the centurion's words (he is not worthy..).The example of the publican and the Pharisee. One of the thieves on the cross.Apostle Paul called himself the chief of sinners.
Sinner's prayer can be expressed in non verbal ways like Zaccheus, Mary Magdalene etc. Jesus says " sin no more".
What am i saying is the sinner's prayer is not written in stone but one of the ways to express repentance.
Our Lord looks at the heart, so if we have to pray the sinner's prayer, let it be from the heart.
Bottom line, it is God who saves us. God leads us to repentance.