1. If no person appears to contest the probate of a will, the court may admit it to probate on the testimony of only one of the subscribing witnesses, if that testimony shows that the will was executed in all particulars as required by law, and that the testator was of sound mind and had attained the age of 18 years at the time of its execution.
2. A filed affidavit of the witness, showing that the will was executed in all particulars as required by law, and that the testator was of sound mind and had attained the age of 18 years at the time of its execution, must be received in evidence and has the same force and effect as if the witness were present and testified orally.