First of all; Tolerance has nothing to do with the forgiveness of sin.
The propitiation for the sins of mankind Christ PAID in FULL. God accepts that payment on behalf of all those who believe in Christ. There is no "tolerance" of sin involved.
Secondly; Your claim that Christ's mercy "does not extend to continued sin" is absolutely unscriptural.
It suggests that Christians must become sinless from the moment they profess faith in Christ until the day they die, or Christ will take back his salvation and they will go to Hell.
How awful. And how totally unscriptural.
The New Testament is full of admonitions directed to the Church regarding sin...making it clear that Christians can and do commit sins.