add following lines below "export PATH="$PATH:$HOME/.rvm/bin" # Add RVM to PATH for scripting" into ~/.profile
export GEM_HOME="/Users/spond/.rvm/gems/ruby-2.3.1"
export GEM_PATH="/Users/spond/.rvm/gems/ruby-2.3.1:/Users/spond/.rvm/gems/ruby-2.3.1@global"
export PATH="/Users/spond/.rvm/gems/ruby-2.3.1/bin:/Users/spond/.rvm/gems/ruby-2.3.1@global/bin:/Users/spond/.rvm/rubies/ruby-2.3.1/bin:$PATH"
then run command:
source ~/.bash_profiile
make sure that the GEM_HOME at the first location of PATH.