I have served as an elder at our Christian Church for quite some time. In our system, the Board selects the top candidate from those that are interviewed. You might have some type of method in order to narrow down your choice to 1 candidate.
What your Constitution is stating is that when the candidate is brought before the Church for consideration, they have to receive the approval of 75% of the congregation. This typically occurs when you have just the one candidate that your selection process has narrowed it down to beforehand.
It is not a common practice to have the congregation select from multiple choices (like in an election for a political figure) - as I said, the process usually is done with the leadership of the church going through the possible Pastors and narrowing it down to their top selection. This person then visits the Church and gives a sample "message" to the Church and has the opportunity to meet with the congregation in advance of the approval process.
If that person receives the 75% approval of the congregation, then they are the new pastor. If they do not, then the leadership chooses another person to bring before the Church for approval.
I hope that helps and it is the common way that I have seen this process occur in the Church.
All the best and have a wonderful week.
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