There is no character limit on emails sent from either the Portal or InFellowship.
Updated
<% if (previousArticle) { %>
<% } %>
<% if (allItems.length > 1) { %>
<% if (previousTitle) { %>
<% } %>
<% if (nextArticle) { %>
<%= previousTitle %>
<% } %> <%= previousArticle.title %>
<% if (nextTitle) { %>
<% } %>